diff --git a/otp/userdb.rb b/otp/userdb.rb
index bf0d777..46a2d41 100644
--- a/otp/userdb.rb
+++ b/otp/userdb.rb
@@ -82,7 +82,7 @@
   def confirmUserAdd(user)
     r = @db.execute("SELECT user from users WHERE user=?", user)
     if !r[0]
-      @db.execute("INSERT INTO users(user) VALUES=?", user)
+      @db.execute("INSERT INTO users(user) VALUES(?)", user)
     end
   end
   def authTmpKey(user, tmpkey, code)	# tmpkeyとパスコードの組み合わせで認証