diff --git a/source/lmp/pair_deepmd.cpp b/source/lmp/pair_deepmd.cpp
index b9793ff7f9..22a0449b19 100644
--- a/source/lmp/pair_deepmd.cpp
+++ b/source/lmp/pair_deepmd.cpp
@@ -1,4 +1,5 @@
 #include <iostream>
+#include <sstream>
 #include <string.h>
 #include <iomanip>
 #include <limits>