diff --git a/web3/_utils/module_testing/eth_module.py b/web3/_utils/module_testing/eth_module.py
index e0c630a0d4..f6597dc6f5 100644
--- a/web3/_utils/module_testing/eth_module.py
+++ b/web3/_utils/module_testing/eth_module.py
@@ -688,6 +688,29 @@ def gas_price_strategy(w3: "Web3", txn: TxParams) -> Wei:
         assert txn["gasPrice"] == two_gwei_in_wei
         async_w3.eth.set_gas_price_strategy(None)  # reset strategy
 
+    @pytest.mark.asyncio
+    async def test_gas_price_strategy_middleware_hex_value(
+        self, async_w3: "AsyncWeb3", async_unlocked_account_dual_type: ChecksumAddress
+    ) -> None:
+        txn_params: TxParams = {
+            "from": async_unlocked_account_dual_type,
+            "to": async_unlocked_account_dual_type,
+            "value": Wei(1),
+            "gas": 21000,
+        }
+        two_gwei_in_wei = async_w3.to_wei(2, "gwei")
+
+        def gas_price_strategy(_w3: "Web3", _txn: TxParams) -> str:
+            return hex(two_gwei_in_wei)
+
+        async_w3.eth.set_gas_price_strategy(gas_price_strategy)  # type: ignore
+
+        txn_hash = await async_w3.eth.send_transaction(txn_params)
+        txn = await async_w3.eth.get_transaction(txn_hash)
+
+        assert txn["gasPrice"] == two_gwei_in_wei
+        async_w3.eth.set_gas_price_strategy(None)  # reset strategy
+
     @pytest.mark.asyncio
     @pytest.mark.parametrize(
         "max_fee", (1000000000, None), ids=["with_max_fee", "without_max_fee"]
@@ -3199,6 +3222,29 @@ def gas_price_strategy(_w3: "Web3", _txn: TxParams) -> Wei:
 
         w3.eth.set_gas_price_strategy(None)  # reset strategy
 
+    @pytest.mark.asyncio
+    def test_gas_price_strategy_middleware_hex_value(
+        self, w3: "Web3", unlocked_account_dual_type: ChecksumAddress
+    ) -> None:
+        txn_params: TxParams = {
+            "from": unlocked_account_dual_type,
+            "to": unlocked_account_dual_type,
+            "value": Wei(1),
+            "gas": 21000,
+        }
+        two_gwei_in_wei = w3.to_wei(2, "gwei")
+
+        def gas_price_strategy(_w3: "Web3", _txn: TxParams) -> str:
+            return hex(two_gwei_in_wei)
+
+        w3.eth.set_gas_price_strategy(gas_price_strategy)  # type: ignore
+
+        txn_hash = w3.eth.send_transaction(txn_params)
+        txn = w3.eth.get_transaction(txn_hash)
+
+        assert txn["gasPrice"] == two_gwei_in_wei
+        w3.eth.set_gas_price_strategy(None)  # reset strategy
+
     def test_eth_replace_transaction_legacy(
         self, w3: "Web3", unlocked_account_dual_type: ChecksumAddress
     ) -> None:
diff --git a/web3/middleware/gas_price_strategy.py b/web3/middleware/gas_price_strategy.py
index 29c20dabc2..1cd5a31f09 100644
--- a/web3/middleware/gas_price_strategy.py
+++ b/web3/middleware/gas_price_strategy.py
@@ -7,10 +7,10 @@
 from eth_utils.toolz import (
     assoc,
 )
+
 from web3._utils.method_formatters import (
-    to_integer_if_hex,
+    to_hex_if_integer,
 )
-
 from web3._utils.utility_methods import (
     all_in_dict,
     any_in_dict,
@@ -49,7 +49,7 @@ def validate_transaction_params(
         and none_in_dict(DYNAMIC_FEE_TXN_PARAMS, transaction)
     ):
         transaction = assoc(
-            transaction, "gasPrice", to_integer_if_hex(strategy_based_gas_price)
+            transaction, "gasPrice", to_hex_if_integer(strategy_based_gas_price)
         )
 
     # legacy and dynamic fee tx variables used: