diff --git a/protocol/src/types/primitive.rs b/protocol/src/types/primitive.rs
index 26cfb7186..84886929e 100644
--- a/protocol/src/types/primitive.rs
+++ b/protocol/src/types/primitive.rs
@@ -152,7 +152,8 @@ impl<'de> Deserialize<'de> for Hex {
     where
         D: de::Deserializer<'de>,
     {
-        Ok(Hex(withpfx_lowercase::deserialize(deserializer)?))
+        String::deserialize(deserializer)
+            .and_then(|s| Hex::from_str(&s).map_err(serde::de::Error::custom))
     }
 }
 
@@ -534,6 +535,20 @@ mod tests {
         );
     }
 
+    #[test]
+    fn test_hex_serde_deserialize() {
+        #[derive(Deserialize)]
+        struct Params {
+            key: Hex,
+        }
+        let test_params: &str = r#"
+            key = "0x1234"
+        "#;
+        let params: Params = toml::from_str(test_params).unwrap();
+        let expected = Hex::from_str("0x1234").unwrap();
+        assert_eq!(params.key, expected);
+    }
+
     #[test]
     fn test_default_values() {
         let bytes = Hex::empty();