To provide a mounting device for a hydraulic damper capable of achieving sound-proofing effect without inserting a sound-proofing sheet, reducing the number of parts, improving fitting performance, and achieving excellent economy.

A car body mounting bracket 9 is installed on an outer end of a piston rod 2 through rubber bushes 6 and 7, a circular elastic seal 10 is placed to an upper surface roughly at a center of the car body mounting bracket, and a car body frame 3 is placed and coupled on the car body mounting bracket to hold the elastic seal inside in this mounting device for a hydraulic damper. A horizontal baffle plate 15 is protruded from an outer edge of the elastic seal around the elastic seal at a position where the car body frame is applied to the car body mounting bracket when a car body is vibrated.