diff --git a/include/mbedtls/asn1write.h b/include/mbedtls/asn1write.h
index 5554720..e6f0479 100644
--- a/include/mbedtls/asn1write.h
+++ b/include/mbedtls/asn1write.h
@@ -352,7 +352,7 @@
  *                  the existing buffer to fit \p val_len.
  *
  * \return          A pointer to the new / existing entry on success.
- * \return          \c NULL if if there was a memory allocation error.
+ * \return          \c NULL if there was a memory allocation error.
  */
 mbedtls_asn1_named_data *mbedtls_asn1_store_named_data( mbedtls_asn1_named_data **list,
                                         const char *oid, size_t oid_len,