diff --git a/CMakeLists.txt b/CMakeLists.txt
index 1a537c4..ad8f517 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -21,9 +21,9 @@ cmake_minimum_required(VERSION 3.16)
 set(GROONGA_NORMALIZER_MYSQL_PROJECT_NAME "groonga-normalizer-mysql")
 project("${GROONGA_NORMALIZER_MYSQL_PROJECT_NAME}")
 
-if(NOT DEFINED GROONGA_NORMALIZER_MYSQL_DATA_DIR)
-  set(GROONGA_NORMALIZER_MYSQL_DATA_DIR
-    "share/${GROONGA_NORMALIZER_MYSQL_PROJECT_NAME}")
+if(NOT DEFINED GROONGA_NORMALIZER_MYSQL_DOC_DIR)
+  set(GROONGA_NORMALIZER_MYSQL_DOC_DIR
+    "share/doc/${GROONGA_NORMALIZER_MYSQL_PROJECT_NAME}")
 endif()
 
 if(DEFINED GROONGA_NORMALIZER_MYSQL_EMBED)
@@ -100,4 +100,4 @@ endif()
 install(FILES
   "README.md"
   "doc/text/lgpl-2.0.txt"
-  DESTINATION "${GROONGA_NORMALIZER_MYSQL_DATA_DIR}")
+  DESTINATION "${GROONGA_NORMALIZER_MYSQL_DOC_DIR}")