diff --git a/apisix/plugins/ai-proxy/base.lua b/apisix/plugins/ai-proxy/base.lua
index 97c980dc5028..55130f4728b6 100644
--- a/apisix/plugins/ai-proxy/base.lua
+++ b/apisix/plugins/ai-proxy/base.lua
@@ -338,6 +338,8 @@ function _M.before_proxy(conf, ctx, on_error)
                 if res._httpc then
                     res._httpc:close()
                 end
+                core.log.warn("upstream AI service returned status: ", res.status,
+                             ", body: ", error_body or "")
                 return res.status, error_body
             end
 
diff --git a/t/plugin/ai-proxy.t b/t/plugin/ai-proxy.t
index 24658a5b792c..0c51952a770d 100644
--- a/t/plugin/ai-proxy.t
+++ b/t/plugin/ai-proxy.t
@@ -1325,5 +1325,7 @@ POST /anything
 { "messages": [ { "role": "user", "content": "What is 1+1?"} ] }
 --- error_code: 500
 --- response_body_like: upstream boom
+--- error_log
+upstream AI service returned status: 500
 --- response_headers
 Content-Type: application/json