A convertible vacuum cleaner has a nozzle comprising a suction port; a cleaner body having a filter housing in which a filter is mounted, and a motor housing in which a motor is mounted, the cleaner body for being removably connected with the nozzle, the suction port being connected with the filter when the cleaner body is connected with the nozzle; a locking member slidably disposed on a side of the nozzle; a slot formed in the motor housing for receiving the locking member and thereby preventing the cleaner body from separating from the nozzle; and a unlocking means for sliding out the locking member from the slot. By sliding the locking member, which is slidably disposed in the nozzle, into or out from the slot of the cleaner body, the nozzle and the cleaner body can be connected or disconnected simply.