An electronic device (100) using a cover mechanism (30) to cover its hole (14) of its housing (10) is described. The cover mechanism includes a cover (20) and a locking structure (11). The cover has a latching portion (23) and a locking portion (21), both of which include a resilient part. The locking structure is configured for associating with the locking portion and the latching portion. Thus, the cover is latched to the housing to cover the hole by deforming the resilient parts. After the cover is unlatched from the housing by a sudden pulling force, the locking portion still physically connects to the locking structure. After the cover is unlatched from the housing by a normal pulling force, the locking portion has no physically relationship with the locking structure.