diff --git a/meta-ohos-core/recipes-devtools/flex/flex_%.bbappend b/meta-ohos-core/recipes-devtools/flex/flex_%.bbappend
new file mode 100644
index 0000000000000000000000000000000000000000..6896e0d71c13028923a90dfe977d7debdce09ffc
--- /dev/null
+++ b/meta-ohos-core/recipes-devtools/flex/flex_%.bbappend
@@ -0,0 +1,11 @@
+# SPDX-FileCopyrightText: Huawei Inc.
+# SPDX-License-Identifier: Apache-2.0
+
+# flex uses non-literal format strings in a few places.
+# This has been verified to be harmless in 2.6.4.
+#
+# Removing -Werror=format-nonliteral here allows us to use
+# -Werror=format-nonliteral globally in OPTIMIZE_FOR=security mode
+# while keeping flex building.
+
+TARGET_CFLAGS_remove = "-Werror=format-nonliteral"