The invention discloses a sleeve device easy to insert and pull. The sleeve device comprises a front nut, a sleeve and a rear nut, wherein the front nut is in threaded connection with the sleeve. Thesleeve device has the advantages that when the sleeve is inserted or pulled an operation part connected with a 50-core plug is moved outside a transmitting box body, the problem that operation space is small is solved; meanwhile, the area of a designed handheld contract part of the sleeve which is inserted or pulled is enlarged, and it is easy for an operator to perform connection by force; the front nut of the sleeve which is inserted or pulled is matched with a socket shell through a light hole in the front end of the front nut, a guide function during butt-joint of the plug and a socket isachieved, the problems that guide length is insufficient, and it is difficult to make alignment between the 50-core plug and the socket in the axial direction are solved, the risk that an insertion pin is impacted to be bent is relieved, meanwhile the adverse influence of cable gravity on the butt-joint of the plug and the socket is relieved, and the smoothness of plug connection can be greatly improved; since axial alignment is realized, the problem that an accessory clamp spring on the tail of the plug is misplaced is solved at the same time; and it also can be ensured that the accessory clamp spring on the tail is not misplaced.