The invention provides a telescopic sliding top cover device for a truck and a truck. The telescopic sliding top cover device is arranged at the top of the truck and used for opening or covering the top of a compartment. The telescopic sliding top cover device comprises a top cover mechanism, a transmission mechanism and a horizontal pushing mechanism, wherein the top cover mechanism is selectively arranged at the top of the compartment in a covering mode, one end of the top cover mechanism is located at the front end of the compartment, the transmission mechanism comprises a drive part and a transmission part, the transmission part moves under the effect of the drive part, and the horizontal pushing mechanism is connected with the other end of the top cover mechanism and the transmission part, and can move between the front end and the rear end of the compartment under driving of the transmission part so as to push the top cover mechanism to move at the top of the compartment to cover the top of the compartment in an unfolded state or open the top of the compartment in a folded state. The top cover mechanism is driven to move in a folded or unfolded mode so as to open or cover the top of the compartment, and operation convenience and safety are improved.