Imaging devices and medical apparatuses are provided. The imaging device comprises a first cantilever, a second cantilever and an aligning and locking device where the second cantilever is separably connected with the first cantilever, and the aligning and locking device is provided at a connection of the first cantilever and the second cantilever and comprises a positioning groove, a positioning block and a locking member. The positioning groove is concavely provided on one of the first cantilever and the second cantilever and the positioning block is convexly provided on the other and extendable into the positioning groove to cooperate with the positioning groove for positioning. A locking groove is concavely provided in the positioning block. The locking member is movably provided in the cantilever on which the positioning groove is provided, and may insert into the locking groove to cooperate with the locking groove for locking.