Abstract: A lock device for exhibit framework has a lock shell (1), a lock plate (2) and an eccentric lock wheel (3). On the lock plate (2) there are two long grooves with different width extending to front end of forming there prongs with different width thereof. The front end of every prong is respectively made into claw (21, 22, 23), with opposite directions other. The rear end of lock is curved into the form of U-shaped half loop (26), which is a plane on the end surface (261). The support structure consists of three respective oblique planes (231, 211, 221) of the three prongs and relative oblique bearing surface (131, 131, 111) in the front of the lock shell (1), furthermore, the stop structure consists of a stop dent (27) of the lock plate (2) and an eccentric cam (332) of the eccentric lock wheel (3).