A mechanical key code verification system including a mechanical key and a lock apparatus into which the mechanical key is inserted. The mechanical key includes a key body. A key code pattern formed on the key body includes a plurality of recessed portions and a plurality of non-recessed portions. A wireless communication mechanism is incorporated in the key body which performs wireless communication with a communication device. The wireless communication device including an antenna arranged on the key body. The lock apparatus mechanically verifies the key code pattern of the mechanical key when the mechanical key is inserted therein. The recessed portions of the key code pattern of the mechanical key is located inward from the antenna on the key body.