diff --git a/contrib/jemalloc/include/jemalloc/jemalloc_FreeBSD.h b/contrib/jemalloc/include/jemalloc/jemalloc_FreeBSD.h
index 2c5797fde876..9efab93969a5 100644
--- a/contrib/jemalloc/include/jemalloc/jemalloc_FreeBSD.h
+++ b/contrib/jemalloc/include/jemalloc/jemalloc_FreeBSD.h
@@ -41,8 +41,12 @@
 #  define LG_SIZEOF_PTR		2
 #endif
 #ifdef __mips__
+#ifdef __mips_n64
+#  define LG_SIZEOF_PTR		3
+#else
 #  define LG_SIZEOF_PTR		2
 #endif
+#endif
 #ifdef __powerpc64__
 #  define LG_SIZEOF_PTR		3
 #elif defined(__powerpc__)