An unmanned aerial vehicle includes a fuselage and an arm coupled to the fuselage. The arm includes a first segment, a second segment, and a connecting assembly coupling and locking the first segment and the second segment to each other. The connecting assembly includes a first connecting member and a second connecting member. The first connecting member is rotatably coupled to one of the first segment or the second segment. The second connecting member is coupled to another one of the first segment or the second segment. The first connecting member is rotatable relative to the arm and engages with the second connecting member to lock the first segment and the second segment.