To provide a manufacturing method for a viscous fluid sealing damper preventing vibration of and supporting an on-vehicle disc player which dispenses with the insertion work for inserting a damper body of a mounting shaft body into an insertion hole which has been conventionally difficult work and obtains satisfactory damping characteristic.

When manufacturing this viscous fluid sealing damper 16 provided with the damper body 18 which is provided with a thin-walled flexible part 30 and a cylindrical bottomed stirring part 28 and in which viscous fluid 22 is sealed and the shaft body 20 inserted into the insertion hole 44 in the stirring part 28, the shaft body 20 is molded by a hard resin material and the stirring part 28 and the flexible part 30 are molded by a soft resin material, respectively. When molding them, the shaft body 20 is first molded, and then the stirring part 28 and the flexible part 30 are molded into a condition in which the shaft body 20 is inserted into the insertion hole 44 and the shaft body 20, the stirring part 28, and the flexible part 30 are not joined.