A cylinder housing arrangement, where the cylinder housing encloses a lock cylinder or the like, which comprises a number of locking elements to be arranged by a key, preferably tumbler discs to be turned by a key, which discs in their locked position prevent the turning of the lock cylinder relative to the cylinder housing. The cylinder housing comprises a body part and a separate cover part, which is arranged to be installed in the crosswise direction relative to the cylinder housing at the end of the body part on the inserting side of a key, so that it is locked to the body part in the axial direction of the cylinder housing.