diff --git a/net/gclient/gclient_request.go b/net/gclient/gclient_request.go
index be63859a08a..8375f30cf63 100644
--- a/net/gclient/gclient_request.go
+++ b/net/gclient/gclient_request.go
@@ -10,6 +10,7 @@ import (
 	"bytes"
 	"context"
 	"io"
+	"mime"
 	"mime/multipart"
 	"net/http"
 	"os"
@@ -172,7 +173,12 @@ func (c *Client) prepareRequest(ctx context.Context, method, url string, data ..
 		allowFileUploading = true
 	)
 	if len(data) > 0 {
-		switch c.header[httpHeaderContentType] {
+		mediaType, _, err := mime.ParseMediaType(c.header[httpHeaderContentType])
+		if err != nil {
+			// Fallback: use the raw header value if parsing fails.
+			mediaType = c.header[httpHeaderContentType]
+		}
+		switch mediaType {
 		case httpHeaderContentTypeJson:
 			switch data[0].(type) {
 			case string, []byte:
@@ -206,7 +212,12 @@ func (c *Client) prepareRequest(ctx context.Context, method, url string, data ..
 	if method == http.MethodGet {
 		var bodyBuffer *bytes.Buffer
 		if params != "" {
-			switch c.header[httpHeaderContentType] {
+			mediaType, _, err := mime.ParseMediaType(c.header[httpHeaderContentType])
+			if err != nil {
+				// Fallback: use the raw header value if parsing fails.
+				mediaType = c.header[httpHeaderContentType]
+			}
+			switch mediaType {
 			case
 				httpHeaderContentTypeJson,
 				httpHeaderContentTypeXml: