To provide a retractable mud guard having a mud guard body retracted in a tail lamp when it may get a damage or it becomes an obstacle in rearward operation and extended for use as a mud guard when a vehicle travels on a general road.

A cover (rail) having a length equal to that of the mud guard body 1 is installed in the tail lamp 2. A roller motor 3 is attached to a damp side chassis. A switch capable of increasing or decreasing the force of the roller motor is mounted at an operator's seat. A plate for preventing the mud guard body 1 from being excessively raised is installed on the lower side of the mud guard body.