diff --git a/net/curl.cpp b/net/curl.cpp
index 6906f43d..8445ae41 100644
--- a/net/curl.cpp
+++ b/net/curl.cpp
@@ -19,6 +19,7 @@ limitations under the License.
 #include <shared_mutex>
 #include <vector>
 #include <memory>
+#include <sstream>
 
 #include <photon/common/alog.h>
 #include <photon/common/event-loop.h>