Double-system lock

The utility model provides a double-system lock, which comprises a lock shell, a combination lock mechanism and a key lock mechanism, wherein, the lock shell is provided with a panel; a retaining wall is arranged on the inner side of the panel in a protruding manner; the combination lock mechanism provided with a plurality of number wheels is mounted in the lock shell; a wheel sleeve is sleeved on each number wheel in a hinged manner; the number wheels are sleeved together by a lock cylinder rod penetrating the number wheel; a spring is sleeved between each two wheel sleeves; a plane surface part and a lug are formed on each end of each wheel sleeve; and when the number wheel is not rotated to a right position, the retaining wall is retained in the lug of a shaft sleeve. Therefore, a user can lock or change a number only by utilizing the right number.