diff --git a/bigquery/storage/managedwriter/adapt/protoconversion.go b/bigquery/storage/managedwriter/adapt/protoconversion.go
index 411febd24308..5cc00c2ed17d 100644
--- a/bigquery/storage/managedwriter/adapt/protoconversion.go
+++ b/bigquery/storage/managedwriter/adapt/protoconversion.go
@@ -63,6 +63,7 @@ var bqTypeToFieldTypeMap = map[storagepb.TableFieldSchema_Type]descriptorpb.Fiel
 	storagepb.TableFieldSchema_TIME:       descriptorpb.FieldDescriptorProto_TYPE_INT64,
 	storagepb.TableFieldSchema_TIMESTAMP:  descriptorpb.FieldDescriptorProto_TYPE_INT64,
 	storagepb.TableFieldSchema_RANGE:      descriptorpb.FieldDescriptorProto_TYPE_MESSAGE,
+	storagepb.TableFieldSchema_JSON:       descriptorpb.FieldDescriptorProto_TYPE_STRING,
 }
 
 var allowedRangeTypes = []storagepb.TableFieldSchema_Type{
@@ -107,6 +108,7 @@ var bqTypeToWrapperMap = map[storagepb.TableFieldSchema_Type]string{
 	storagepb.TableFieldSchema_STRING:     ".google.protobuf.StringValue",
 	storagepb.TableFieldSchema_TIME:       ".google.protobuf.Int64Value",
 	storagepb.TableFieldSchema_TIMESTAMP:  ".google.protobuf.Int64Value",
+	storagepb.TableFieldSchema_JSON:       ".google.protobuf.StringValue",
 }
 
 // filename used by well known types proto
diff --git a/bigquery/storage/managedwriter/adapt/protoconversion_test.go b/bigquery/storage/managedwriter/adapt/protoconversion_test.go
index be15ab19d30b..73f9ebbb134d 100644
--- a/bigquery/storage/managedwriter/adapt/protoconversion_test.go
+++ b/bigquery/storage/managedwriter/adapt/protoconversion_test.go
@@ -100,6 +100,65 @@ func TestSchemaToProtoConversion(t *testing.T) {
 				},
 			},
 		},
+		{
+			description: "json type",
+			bq: &storagepb.TableSchema{
+				Fields: []*storagepb.TableFieldSchema{
+					{Name: "json_required", Type: storagepb.TableFieldSchema_JSON, Mode: storagepb.TableFieldSchema_REQUIRED},
+					{Name: "json_optional", Type: storagepb.TableFieldSchema_JSON, Mode: storagepb.TableFieldSchema_NULLABLE},
+				}},
+			wantProto2: &descriptorpb.DescriptorProto{
+				Name: proto.String("root"),
+				Field: []*descriptorpb.FieldDescriptorProto{
+					{
+						Name:   proto.String("json_required"),
+						Number: proto.Int32(1),
+						Type:   descriptorpb.FieldDescriptorProto_TYPE_STRING.Enum(),
+						Label:  descriptorpb.FieldDescriptorProto_LABEL_REQUIRED.Enum()},
+					{
+						Name:   proto.String("json_optional"),
+						Number: proto.Int32(2),
+						Type:   descriptorpb.FieldDescriptorProto_TYPE_STRING.Enum(),
+						Label:  descriptorpb.FieldDescriptorProto_LABEL_OPTIONAL.Enum(),
+					},
+				},
+			},
+			wantProto2Normalized: &descriptorpb.DescriptorProto{
+				Name: proto.String("root"),
+				Field: []*descriptorpb.FieldDescriptorProto{
+					{
+						Name:   proto.String("json_required"),
+						Number: proto.Int32(1),
+						Type:   descriptorpb.FieldDescriptorProto_TYPE_STRING.Enum(),
+						Label:  descriptorpb.FieldDescriptorProto_LABEL_REQUIRED.Enum(),
+					},
+					{
+						Name:   proto.String("json_optional"),
+						Number: proto.Int32(2),
+						Type:   descriptorpb.FieldDescriptorProto_TYPE_STRING.Enum(),
+						Label:  descriptorpb.FieldDescriptorProto_LABEL_OPTIONAL.Enum(),
+					},
+				},
+			},
+			wantProto3: &descriptorpb.DescriptorProto{
+				Name: proto.String("root"),
+				Field: []*descriptorpb.FieldDescriptorProto{
+					{
+						Name:   proto.String("json_required"),
+						Number: proto.Int32(1),
+						Type:   descriptorpb.FieldDescriptorProto_TYPE_STRING.Enum(),
+						Label:  descriptorpb.FieldDescriptorProto_LABEL_OPTIONAL.Enum(),
+					},
+					{
+						Name:     proto.String("json_optional"),
+						Number:   proto.Int32(2),
+						Type:     descriptorpb.FieldDescriptorProto_TYPE_MESSAGE.Enum(),
+						TypeName: proto.String(".google.protobuf.StringValue"),
+						Label:    descriptorpb.FieldDescriptorProto_LABEL_OPTIONAL.Enum(),
+					},
+				},
+			},
+		},
 		{
 			// exercise construct of a submessage
 			description: "nested",
@@ -1236,6 +1295,13 @@ func TestNormalizeDescriptor(t *testing.T) {
 						Type:     descriptorpb.FieldDescriptorProto_TYPE_MESSAGE.Enum(),
 						Label:    descriptorpb.FieldDescriptorProto_LABEL_OPTIONAL.Enum(),
 					},
+					{
+						Name:     proto.String("json_type"),
+						JsonName: proto.String("jsonType"),
+						Number:   proto.Int32(4),
+						Type:     descriptorpb.FieldDescriptorProto_TYPE_STRING.Enum(),
+						Label:    descriptorpb.FieldDescriptorProto_LABEL_OPTIONAL.Enum(),
+					},
 				},
 				NestedType: []*descriptorpb.DescriptorProto{
 					{
diff --git a/bigquery/storage/managedwriter/adapt/schemaconversion.go b/bigquery/storage/managedwriter/adapt/schemaconversion.go
index 7cbfa8aa3b58..3e88386169cf 100644
--- a/bigquery/storage/managedwriter/adapt/schemaconversion.go
+++ b/bigquery/storage/managedwriter/adapt/schemaconversion.go
@@ -36,6 +36,7 @@ var fieldTypeMap = map[bigquery.FieldType]storagepb.TableFieldSchema_Type{
 	bigquery.BigNumericFieldType: storagepb.TableFieldSchema_BIGNUMERIC,
 	bigquery.GeographyFieldType:  storagepb.TableFieldSchema_GEOGRAPHY,
 	bigquery.RangeFieldType:      storagepb.TableFieldSchema_RANGE,
+	bigquery.JSONFieldType:       storagepb.TableFieldSchema_JSON,
 }
 
 func bqFieldToProto(in *bigquery.FieldSchema) (*storagepb.TableFieldSchema, error) {
diff --git a/bigquery/storage/managedwriter/adapt/schemaconversion_test.go b/bigquery/storage/managedwriter/adapt/schemaconversion_test.go
index 99ecb4a9a170..ab1a91826da3 100644
--- a/bigquery/storage/managedwriter/adapt/schemaconversion_test.go
+++ b/bigquery/storage/managedwriter/adapt/schemaconversion_test.go
@@ -95,6 +95,21 @@ func TestFieldConversions(t *testing.T) {
 				},
 			},
 		},
+		{
+			desc: "json type",
+			bq: &bigquery.FieldSchema{
+				Name:        "name",
+				Type:        bigquery.JSONFieldType,
+				Description: "description",
+				Required:    true,
+			},
+			proto: &storagepb.TableFieldSchema{
+				Name:        "name",
+				Type:        storagepb.TableFieldSchema_JSON,
+				Description: "description",
+				Mode:        storagepb.TableFieldSchema_REQUIRED,
+			},
+		},
 		{
 			desc: "range type",
 			bq: &bigquery.FieldSchema{
@@ -200,6 +215,17 @@ func TestSchemaConversion(t *testing.T) {
 				},
 			},
 		},
+		{
+			description: "json type",
+			bqSchema: bigquery.Schema{
+				{Name: "json", Type: bigquery.JSONFieldType},
+			},
+			storageSchema: &storagepb.TableSchema{
+				Fields: []*storagepb.TableFieldSchema{
+					{Name: "json", Type: storagepb.TableFieldSchema_JSON, Mode: storagepb.TableFieldSchema_NULLABLE},
+				},
+			},
+		},
 		{
 			description: "range types",
 			bqSchema: bigquery.Schema{
diff --git a/bigquery/storage/managedwriter/integration_test.go b/bigquery/storage/managedwriter/integration_test.go
index 4a7f2470a6ad..199f662cadf5 100644
--- a/bigquery/storage/managedwriter/integration_test.go
+++ b/bigquery/storage/managedwriter/integration_test.go
@@ -229,6 +229,10 @@ func TestIntegration_ManagedWriter(t *testing.T) {
 			t.Parallel()
 			testDefaultStreamDynamicJSON(ctx, t, mwClient, bqClient, dataset)
 		})
+		t.Run("DefaultStreamJSONData", func(t *testing.T) {
+			t.Parallel()
+			testDefaultStreamJSONData(ctx, t, mwClient, bqClient, dataset)
+		})
 		t.Run("CommittedStream", func(t *testing.T) {
 			t.Parallel()
 			testCommittedStream(ctx, t, mwClient, bqClient, dataset)
@@ -455,6 +459,63 @@ func testDefaultStreamDynamicJSON(ctx context.Context, t *testing.T, mwClient *C
 		withDistinctValues("public", int64(2)))
 }
 
+func testDefaultStreamJSONData(ctx context.Context, t *testing.T, mwClient *Client, bqClient *bigquery.Client, dataset *bigquery.Dataset) {
+	testTable := dataset.Table(tableIDs.New())
+	if err := testTable.Create(ctx, &bigquery.TableMetadata{Schema: testdata.ComplexTypeSchema}); err != nil {
+		t.Fatalf("failed to create test table %s: %v", testTable.FullyQualifiedName(), err)
+	}
+
+	md, descriptorProto := setupDynamicDescriptors(t, testdata.ComplexTypeSchema)
+
+	ms, err := mwClient.NewManagedStream(ctx,
+		WithDestinationTable(TableParentFromParts(testTable.ProjectID, testTable.DatasetID, testTable.TableID)),
+		WithType(DefaultStream),
+		WithSchemaDescriptor(descriptorProto),
+	)
+	if err != nil {
+		t.Fatalf("NewManagedStream: %v", err)
+	}
+	validateTableConstraints(ctx, t, bqClient, testTable, "before send",
+		withExactRowCount(0))
+
+	sampleJSONData := [][]byte{
+		[]byte(`{"json_type":"{\"foo\": \"bar\"}"}`),
+		[]byte(`{"json_type":"{\"key\": \"value\"}"}`),
+		[]byte(`{"json_type":"\"a string\""}`),
+	}
+
+	var result *AppendResult
+	for k, v := range sampleJSONData {
+		message := dynamicpb.NewMessage(md)
+
+		// First, json->proto message
+		err = protojson.Unmarshal(v, message)
+		if err != nil {
+			t.Fatalf("failed to Unmarshal json message for row %d: %v", k, err)
+		}
+		// Then, proto message -> bytes.
+		b, err := proto.Marshal(message)
+		if err != nil {
+			t.Fatalf("failed to marshal proto bytes for row %d: %v", k, err)
+		}
+		result, err = ms.AppendRows(ctx, [][]byte{b})
+		if err != nil {
+			t.Errorf("single-row append %d failed: %v", k, err)
+		}
+	}
+
+	// Wait for the result to indicate ready, then validate.
+	o, err := result.GetResult(ctx)
+	if err != nil {
+		t.Errorf("result error for last send: %v", err)
+	}
+	if o != NoStreamOffset {
+		t.Errorf("offset mismatch, got %d want %d", o, NoStreamOffset)
+	}
+	validateTableConstraints(ctx, t, bqClient, testTable, "after send",
+		withExactRowCount(int64(len(sampleJSONData))))
+}
+
 func testBufferedStream(ctx context.Context, t *testing.T, mwClient *Client, bqClient *bigquery.Client, dataset *bigquery.Dataset) {
 	testTable := dataset.Table(tableIDs.New())
 	if err := testTable.Create(ctx, &bigquery.TableMetadata{Schema: testdata.SimpleMessageSchema}); err != nil {
@@ -1389,6 +1450,7 @@ func TestIntegration_ProtoNormalization(t *testing.T) {
 		t.Run("ComplexType", func(t *testing.T) {
 			t.Parallel()
 			schema := testdata.ComplexTypeSchema
+			jsonData := "{\"foo\": \"bar\"}"
 			mesg := &testdata.ComplexType{
 				NestedRepeatedType: []*testdata.NestedType{
 					{
@@ -1404,6 +1466,7 @@ func TestIntegration_ProtoNormalization(t *testing.T) {
 				RangeType: &testdata.RangeTypeTimestamp{
 					End: proto.Int64(time.Now().UnixNano()),
 				},
+				JsonType: &jsonData,
 			}
 			b, err := proto.Marshal(mesg)
 			if err != nil {
diff --git a/bigquery/storage/managedwriter/testdata/schemas.go b/bigquery/storage/managedwriter/testdata/schemas.go
index 2d76bdf6a181..cd26e15014ad 100644
--- a/bigquery/storage/managedwriter/testdata/schemas.go
+++ b/bigquery/storage/managedwriter/testdata/schemas.go
@@ -99,6 +99,10 @@ var (
 				Type: bigquery.TimestampFieldType,
 			},
 		},
+		{
+			Name: "json_type",
+			Type: bigquery.JSONFieldType,
+		},
 	}
 
 	// We currently follow proto2 rules here, hence the well known types getting treated as records.
diff --git a/bigquery/storage/managedwriter/testdata/testing.pb.go b/bigquery/storage/managedwriter/testdata/testing.pb.go
index d9a580431e88..ea57f7df689a 100644
--- a/bigquery/storage/managedwriter/testdata/testing.pb.go
+++ b/bigquery/storage/managedwriter/testdata/testing.pb.go
@@ -440,6 +440,7 @@ type ComplexType struct {
 	NestedRepeatedType []*NestedType       `protobuf:"bytes,1,rep,name=nested_repeated_type,json=nestedRepeatedType" json:"nested_repeated_type,omitempty"`
 	InnerType          *InnerType          `protobuf:"bytes,2,opt,name=inner_type,json=innerType" json:"inner_type,omitempty"`
 	RangeType          *RangeTypeTimestamp `protobuf:"bytes,3,opt,name=range_type,json=rangeType" json:"range_type,omitempty"`
+	JsonType           *string             `protobuf:"bytes,4,opt,name=json_type,json=jsonType" json:"json_type,omitempty"`
 }
 
 func (x *ComplexType) Reset() {
@@ -495,6 +496,13 @@ func (x *ComplexType) GetRangeType() *RangeTypeTimestamp {
 	return nil
 }
 
+func (x *ComplexType) GetJsonType() string {
+	if x != nil && x.JsonType != nil {
+		return *x.JsonType
+	}
+	return ""
+}
+
 type ContainsRecursive struct {
 	state         protoimpl.MessageState
 	sizeCache     protoimpl.SizeCache
@@ -643,6 +651,7 @@ type WithOneOf struct {
 
 	Int32Value *int32 `protobuf:"varint,1,opt,name=int32_value,json=int32Value" json:"int32_value,omitempty"`
 	// Types that are assignable to OneofValue:
+	//
 	//	*WithOneOf_StringValue
 	//	*WithOneOf_DoubleValue
 	OneofValue isWithOneOf_OneofValue `protobuf_oneof:"oneof_value"`
@@ -952,7 +961,7 @@ var file_testing_proto_rawDesc = []byte{
 	0x52, 0x61, 0x6e, 0x67, 0x65, 0x54, 0x79, 0x70, 0x65, 0x54, 0x69, 0x6d, 0x65, 0x73, 0x74, 0x61,
 	0x6d, 0x70, 0x12, 0x14, 0x0a, 0x05, 0x73, 0x74, 0x61, 0x72, 0x74, 0x18, 0x01, 0x20, 0x01, 0x28,
 	0x03, 0x52, 0x05, 0x73, 0x74, 0x61, 0x72, 0x74, 0x12, 0x10, 0x0a, 0x03, 0x65, 0x6e, 0x64, 0x18,
-	0x02, 0x20, 0x01, 0x28, 0x03, 0x52, 0x03, 0x65, 0x6e, 0x64, 0x22, 0xc6, 0x01, 0x0a, 0x0b, 0x43,
+	0x02, 0x20, 0x01, 0x28, 0x03, 0x52, 0x03, 0x65, 0x6e, 0x64, 0x22, 0xe3, 0x01, 0x0a, 0x0b, 0x43,
 	0x6f, 0x6d, 0x70, 0x6c, 0x65, 0x78, 0x54, 0x79, 0x70, 0x65, 0x12, 0x46, 0x0a, 0x14, 0x6e, 0x65,
 	0x73, 0x74, 0x65, 0x64, 0x5f, 0x72, 0x65, 0x70, 0x65, 0x61, 0x74, 0x65, 0x64, 0x5f, 0x74, 0x79,
 	0x70, 0x65, 0x18, 0x01, 0x20, 0x03, 0x28, 0x0b, 0x32, 0x14, 0x2e, 0x74, 0x65, 0x73, 0x74, 0x64,
@@ -965,61 +974,63 @@ var file_testing_proto_rawDesc = []byte{
 	0x74, 0x79, 0x70, 0x65, 0x18, 0x03, 0x20, 0x01, 0x28, 0x0b, 0x32, 0x1c, 0x2e, 0x74, 0x65, 0x73,
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 }
 
 var (
diff --git a/bigquery/storage/managedwriter/testdata/testing.proto b/bigquery/storage/managedwriter/testdata/testing.proto
index 6012e9bc0e63..a317e1acb7bd 100644
--- a/bigquery/storage/managedwriter/testdata/testing.proto
+++ b/bigquery/storage/managedwriter/testdata/testing.proto
@@ -60,6 +60,7 @@ message ComplexType {
   repeated NestedType nested_repeated_type = 1;
   optional InnerType inner_type = 2;
   optional RangeTypeTimestamp range_type = 3;
+  optional string json_type = 4;
 }
 
 message ContainsRecursive {