diff --git a/sections.go b/sections.go
index cde7ec7..61e8f95 100644
--- a/sections.go
+++ b/sections.go
@@ -83,8 +83,7 @@ func (c *Client) CreateSection(
 
 func (c *Client) UpdateSection(
 	ctx context.Context, oauth2Token *oauth2.Token,
-	params SectionParams,
-	sectionID uint32,
+	sectionID uint32, params SectionParams,
 ) (*Section, *oauth2.Token, error) {
 	var result SectionResponse
 	oauth2Token, err := c.call(ctx, path.Join(APIPathSections, fmt.Sprint(sectionID)), http.MethodPut, oauth2Token, nil, params, &result)
diff --git a/segment_tags.go b/segment_tags.go
index 13a14b9..4cd16e3 100644
--- a/segment_tags.go
+++ b/segment_tags.go
@@ -21,6 +21,10 @@ type SegmentTags struct {
 	SegmentTags []SegmentTag `json:"segment_tags"`
 }
 
+type SegmentTagResponse struct {
+	SegmentTag SegmentTag `json:"segment_tag"`
+}
+
 type SegmentTag struct {
 	// セグメントタグID
 	ID int32 `json:"id"`
@@ -34,6 +38,19 @@ type SegmentTag struct {
 	Shortcut2 *string `json:"shortcut2"`
 }
 
+type SegmentTagParams struct {
+	// 事業所ID
+	CompanyID int32 `json:"company_id"`
+	// セグメントタグ名 (30文字以内)
+	Name string `json:"name"`
+	// 備考 (30文字以内)
+	Description *string `json:"description,omitempty"`
+	// ショートカット１ (20文字以内)
+	Shortcut1 *string `json:"shortcut1,omitempty"`
+	// ショートカット２ (20文字以内)
+	Shortcut2 *string `json:"shortcut2,omitempty"`
+}
+
 type GetSegmentTagsOpts struct {
 	Offset uint32 `url:"offset,omitempty"`
 	Limit  uint32 `url:"limit,omitempty"`
@@ -41,7 +58,8 @@ type GetSegmentTagsOpts struct {
 
 func (c *Client) GetSegmentTags(
 	ctx context.Context, oauth2Token *oauth2.Token,
-	companyID uint32, tagID uint32, opts GetSegmentTagsOpts,
+	companyID uint32, segmentID uint32,
+	opts GetSegmentTagsOpts,
 ) (*SegmentTags, *oauth2.Token, error) {
 	var result SegmentTags
 
@@ -50,10 +68,53 @@ func (c *Client) GetSegmentTags(
 		return nil, oauth2Token, err
 	}
 	SetCompanyID(&v, companyID)
-	oauth2Token, err = c.call(ctx, path.Join(APIPathSegments, fmt.Sprint(tagID), "tags"), http.MethodGet, oauth2Token, v, nil, &result)
+	oauth2Token, err = c.call(ctx, path.Join(APIPathSegments, fmt.Sprint(segmentID), "tags"), http.MethodGet, oauth2Token, v, nil, &result)
 	if err != nil {
 		return nil, oauth2Token, err
 	}
 
 	return &result, oauth2Token, nil
 }
+
+func (c *Client) CreateSegmentTag(
+	ctx context.Context, oauth2Token *oauth2.Token,
+	segmentID uint32, params SegmentTagParams,
+) (*SegmentTag, *oauth2.Token, error) {
+	var result SegmentTagResponse
+	oauth2Token, err := c.call(ctx, path.Join(APIPathSegments, fmt.Sprint(segmentID), "tags"), http.MethodPost, oauth2Token, nil, params, &result)
+	if err != nil {
+		return nil, oauth2Token, err
+	}
+	return &result.SegmentTag, oauth2Token, nil
+}
+
+func (c *Client) UpdateSegmentTag(
+	ctx context.Context, oauth2Token *oauth2.Token,
+	segmentID uint32, id uint32,
+	params SegmentTagParams,
+) (*SegmentTag, *oauth2.Token, error) {
+	var result SegmentTagResponse
+	oauth2Token, err := c.call(ctx, path.Join(APIPathSegments, fmt.Sprint(segmentID), "tags", fmt.Sprint(id)), http.MethodPut, oauth2Token, nil, params, &result)
+	if err != nil {
+		return nil, oauth2Token, err
+	}
+	return &result.SegmentTag, oauth2Token, nil
+}
+
+func (c *Client) DestroySegmentTag(
+	ctx context.Context, oauth2Token *oauth2.Token,
+	companyID uint32,
+	segmentID uint32, id uint32,
+) (*oauth2.Token, error) {
+	v, err := query.Values(nil)
+	if err != nil {
+		return oauth2Token, err
+	}
+	SetCompanyID(&v, companyID)
+	oauth2Token, err = c.call(ctx, path.Join(APIPathSegments, fmt.Sprint(segmentID), "tags", fmt.Sprint(id)), http.MethodDelete, oauth2Token, v, nil, nil)
+	if err != nil {
+		return oauth2Token, err
+	}
+
+	return oauth2Token, nil
+}
diff --git a/tags.go b/tags.go
index 902e9fe..7822b9d 100644
--- a/tags.go
+++ b/tags.go
@@ -84,8 +84,7 @@ func (c *Client) CreateTag(
 
 func (c *Client) UpdateTag(
 	ctx context.Context, oauth2Token *oauth2.Token,
-	params TagParams,
-	tagID uint32,
+	tagID uint32, params TagParams,
 ) (*Tag, *oauth2.Token, error) {
 	var result TagResponse
 	oauth2Token, err := c.call(ctx, path.Join(APIPathTags, fmt.Sprint(tagID)), http.MethodPut, oauth2Token, nil, params, &result)