diff --git a/include/ceres/ceres.h b/include/ceres/ceres.h
index 41bd649..0b3ae0d 100644
--- a/include/ceres/ceres.h
+++ b/include/ceres/ceres.h
@@ -47,7 +47,6 @@
 #include "ceres/local_parameterization.h"
 #include "ceres/loss_function.h"
 #include "ceres/numeric_diff_cost_function.h"
-#include "ceres/numeric_diff_functor.h"
 #include "ceres/ordered_groups.h"
 #include "ceres/problem.h"
 #include "ceres/sized_cost_function.h"