diff --git a/icu4c/source/tools/toolutil/pkg_genc.cpp b/icu4c/source/tools/toolutil/pkg_genc.cpp
index 98a1a405328..6959071e7cc 100644
--- a/icu4c/source/tools/toolutil/pkg_genc.cpp
+++ b/icu4c/source/tools/toolutil/pkg_genc.cpp
@@ -248,6 +248,15 @@ static const struct AssemblyType {
       "\tALIGN 16\n"
       "_%s\tLABEL DWORD\n",
       "\tDWORD ","\nICUDATA_%s\tENDS\n\tEND\n",HEX_0H
+    },
+    { "masm64",
+      "\tTITLE %s\n"
+      "; generated by genccode\n"
+      "\tPUBLIC _%s\n"
+      "ICUDATA_%s\tSEGMENT READONLY 'DATA'\n"
+      "\tALIGN 16\n"
+      "_%s\tLABEL DWORD\n",
+      "\tDWORD ","\nICUDATA_%s\tENDS\n\tEND\n",HEX_0H
     }
 };