The invention discloses a double-layer sightseeing bus. The bus top of a double-layer sightseeing bus body comprises a movable bus top positioned at the front half part and a fixing bus top positioned at the rear half part; each side wall of the bus body, corresponding to the movable bus top, of an upper layer bus body, is formed up-down butt joint of an upper side wall and a lower side wall; each of lower wall push-and-pull mechanisms and a corresponding upper wall lifting mechanism are arranged in the bus body corresponding to the movable bus top; each of the lower wall push-and-pull mechanisms is used for pulling the corresponding lower side wall to retract to the bus; each of the upper wall lifting mechanisms is used for driving the corresponding upper side wall to fall to the initial position of the corresponding lower side wall; a frame supporting mechanism and a propelling mechanism are arranged at the upper part of each of the upper side walls; a movable sliding rail is supported on each of the frame supporting mechanisms, and the movable bus top is arranged on the movable sliding rails; fixing sliding rails which are parallel to the bus body are arranged at the top of the fixing bus top; and the propelling mechanism is used for propelling the movable bus top to move backwards to the fixing bus top after the movable sliding rails and the fixing sliding rails are in butt joint.