To provide a thrust sliding bearing capable of supporting an end of a piston rod instead of a mounting plate of a mounting mechanism to a vehicle body of a thrust assembly and accordingly, capable of reducing cost by simplifying the mounting mechanism; and a combination mechanism of this thrust sliding bearing and the piston rod.

This thrust sliding bearing 1 is furnished with; a synthetic resin bearing body 4 having a ring upper surface 2 and a ring outer peripheral surface 3; a synthetic resin bearing body 6 overlapping the bearing body 4 free to relatively rotate; a synthetic resin thrust sliding bearing piece 7 interposed between the ring upper surface 2 of the bearing body 4 and a ring lower surface 5 of the bearing body 6; a ring upper cover 10 having a ring engagement inner peripheral surface 9 to be engaged with a ring engagement outer peripheral surface 8 of the bearing body 4 and; a ring plate metal 15 interposed between a ring upper surface 11 of the bearing body 6 and a lower surface 14 of the ring upper cover 10.