diff --git a/tests/suites/test_suite_aes.function b/tests/suites/test_suite_aes.function
index aec4a49..e346dc7 100644
--- a/tests/suites/test_suite_aes.function
+++ b/tests/suites/test_suite_aes.function
@@ -258,6 +258,21 @@
 }
 /* END_CASE */
 
+/* BEGIN_CASE depends_on:MBEDTLS_CIPHER_MODE_XTS */
+void aes_crypt_xts_keysize( int size, int retval )
+{
+    mbedtls_aes_xts_context ctx;
+    const unsigned char *key = NULL;
+    size_t key_len = size;
+
+    mbedtls_aes_xts_init( &ctx );
+
+    TEST_ASSERT( mbedtls_aes_xts_setkey_enc( &ctx, key, key_len * 8 ) == retval );
+    TEST_ASSERT( mbedtls_aes_xts_setkey_dec( &ctx, key, key_len * 8 ) == retval );
+exit:
+    mbedtls_aes_xts_free( &ctx );
+}
+/* END_CASE */
 
 
 /* BEGIN_CASE depends_on:MBEDTLS_CIPHER_MODE_CFB */
diff --git a/tests/suites/test_suite_aes.xts.data b/tests/suites/test_suite_aes.xts.data
index a0a6626..6af5227 100644
--- a/tests/suites/test_suite_aes.xts.data
+++ b/tests/suites/test_suite_aes.xts.data
@@ -13,6 +13,21 @@
 AES-128-XTS Encrypt Fail Sector Too Large (by 1 block)
 aes_crypt_xts_size:16777232:MBEDTLS_ERR_AES_INVALID_INPUT_LENGTH
 
+AES-0-XTS Setkey Fail Invalid Key Length
+aes_crypt_xts_keysize:0:MBEDTLS_ERR_AES_INVALID_KEY_LENGTH
+
+AES-4-XTS Setkey Fail Invalid Key Length
+aes_crypt_xts_keysize:1:MBEDTLS_ERR_AES_INVALID_KEY_LENGTH
+
+AES-64-XTS Setkey Fail Invalid Key Length
+aes_crypt_xts_keysize:16:MBEDTLS_ERR_AES_INVALID_KEY_LENGTH
+
+AES-192-XTS Setkey Fail Invalid Key Length
+aes_crypt_xts_keysize:48:MBEDTLS_ERR_AES_INVALID_KEY_LENGTH
+
+AES-384-XTS Setkey Fail Invalid Key Length
+aes_crypt_xts_keysize:96:MBEDTLS_ERR_AES_INVALID_KEY_LENGTH
+
 AES-128-XTS Encrypt NIST XTSTestVectors #1
 aes_encrypt_xts:"a1b90cba3f06ac353b2c343876081762090923026e91771815f29dab01932f2f":"4faef7117cda59c66e4b92013e768ad5":"ebabce95b14d3c8d6fb350390790311c":"778ae8b43cb98d5a825081d5be471c63"