diff --git a/python/ray/serve/http_adapters.py b/python/ray/serve/http_adapters.py
index 88bddd811..c7423323c 100644
--- a/python/ray/serve/http_adapters.py
+++ b/python/ray/serve/http_adapters.py
@@ -93,4 +93,6 @@ async def pandas_read_json(raw_request: Request):
     import pandas as pd
 
     raw_json = await raw_request.body()
+    if isinstance(raw_json, bytes):
+        raw_json = raw_json.decode("utf-8")
     return pd.read_json(raw_json, **raw_request.query_params)