The invention relates to a mechanical button lock. The mechanical button lock comprises a lock body and a spring bolt and a lock cylinder which are arranged in the lock body; the spring bolt does reciprocating motion relative to the lock body and has a locking position that the spring bolt is extended out of the lock body and an unlocking position that the spring bolt is retracted into the lock body; the movement direction of the lock cylinder is perpendicular to that of the spring bolt, and the lock cylinder has an avoiding position and a locking and stopping position; when the lock cylinder is positioned at the locking and stopping position, the spring bolt is locked at the locking position by combination of the lock cylinder and a locking and stopping structure which is correspondingly arranged on the spring bolt; when the lock cylinder is positioned at the avoiding positioning, the spring bolt moves freely by avoiding of the lock cylinder and the locking and stopping structure which is correspondingly arranged on the spring bolt; a spring bolt spring which is used for applying acting force to the spring bolt to ensure that the spring bolt moves toward the locking position, and a lock cylinder spring which is used for applying action force to the lock cylinder to ensure that the lock cylinder moves toward the locking and stopping position are arranged in the lock body; and one end of the spring bolt, which is extended out of the lock body when the spring bolt is positioned at the locking position, is provided with an inclined surface which is pushed by a corresponding object which moves in a direction perpendicular to the movement direction of the spring bolt into the lock body. According to the mechanical button lock, a battery box of an electric vehicle is automatically replaced by a pure mechanical mode.