diff --git a/core/mapping/unmarshaler.go b/core/mapping/unmarshaler.go
index dbd844b81..8d7839869 100644
--- a/core/mapping/unmarshaler.go
+++ b/core/mapping/unmarshaler.go
@@ -610,19 +610,22 @@ func (u *Unmarshaler) processFieldNotFromString(fieldType reflect.Type, value re
 	case valueKind == reflect.String && typeKind == reflect.Map:
 		return u.fillMapFromString(value, mapValue)
 	case valueKind == reflect.String && typeKind == reflect.Slice:
-		// try to find out if it's a byte slice, golang use []byte Marshal to base64 but there only SliceOf uint8/bytes can convert to []byte
+		// try to find out if it's a byte slice,
 		// more details https://pkg.go.dev/encoding/json#Marshal
-		//> Array and slice values encode as JSON arrays, except that []byte encodes as a base64-encoded string, and a nil slice encodes as the null JSON value.
-		//and also u can find this https://stackoverflow.com/questions/34089750/marshal-byte-to-json-giving-a-strange-string
+		// array and slice values encode as JSON arrays,
+		// except that []byte encodes as a base64-encoded string,
+		// and a nil slice encoded as the null JSON value.
+		// https://stackoverflow.com/questions/34089750/marshal-byte-to-json-giving-a-strange-string
 		if fieldType.Elem().Kind() == reflect.Uint8 {
-			strVal := mapValue.(string)
-			decodedBytes, err := base64.StdEncoding.DecodeString(strVal)
-			// if err !=nil do next
-			if err == nil {
-				value.Set(reflect.ValueOf(decodedBytes))
-				return nil
+			// check whether string type, because the kind of some other types can be string
+			if strVal, ok := mapValue.(string); ok {
+				if decodedBytes, err := base64.StdEncoding.DecodeString(strVal); err == nil {
+					value.Set(reflect.ValueOf(decodedBytes))
+					return nil
+				}
 			}
 		}
+
 		return u.fillSliceFromString(fieldType, value, mapValue, fullName)
 	case valueKind == reflect.String && derefedFieldType == durationType:
 		return fillDurationValue(fieldType, value, mapValue.(string))
@@ -748,15 +751,7 @@ func (u *Unmarshaler) processFieldTextUnmarshaler(fieldType reflect.Type, value
 			return true, tval.UnmarshalText(mv)
 		}
 	}
-	//[]byte
-	if fieldType.Kind() == reflect.Slice && fieldType.Elem().Kind() == reflect.Uint8 {
-		b, err := base64.StdEncoding.DecodeString(mapValue.(string))
-		if err != nil {
-			return false, err
-		}
-		value.SetBytes(b)
-		return true, nil
-	}
+
 	return false, nil
 }
 
diff --git a/core/mapping/unmarshaler_test.go b/core/mapping/unmarshaler_test.go
index edecf9068..3ea666c1b 100644
--- a/core/mapping/unmarshaler_test.go
+++ b/core/mapping/unmarshaler_test.go
@@ -4,7 +4,6 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
-	"github.com/zeromicro/go-zero/core/jsonx"
 	"reflect"
 	"strconv"
 	"strings"
@@ -14,6 +13,7 @@ import (
 
 	"github.com/google/uuid"
 	"github.com/stretchr/testify/assert"
+	"github.com/zeromicro/go-zero/core/jsonx"
 	"github.com/zeromicro/go-zero/core/stringx"
 )
 
@@ -4874,6 +4874,7 @@ func TestUnmarshalJsonReaderMultiArray(t *testing.T) {
 			B [][]string `json:"b"`
 			C []byte     `json:"c"`
 		}
+
 		var res testRes
 		marshal := testRes{
 			A: "133",
diff --git a/rest/httpx/requests_test.go b/rest/httpx/requests_test.go
index 93d9c84d3..a544c2d94 100644
--- a/rest/httpx/requests_test.go
+++ b/rest/httpx/requests_test.go
@@ -516,6 +516,7 @@ func TestParseJsonBody(t *testing.T) {
 		assert.Equal(t, "apple", v[0].Name)
 		assert.Equal(t, 18, v[0].Age)
 	})
+
 	t.Run("bytes field", func(t *testing.T) {
 		type v struct {
 			Signature []byte `json:"signature,optional"`