Damping force adjusting structure of hydraulic shock absorber

A damping force adjusting structure of a hydraulic shock absorber in which an oil liquid is accommodated in a cylinder, a piston provided in an insertion end of a piston rod inserted to the cylinder is slidably fitted and inserted to the cylinder, a damping force is generated by controlling an oil liquid flow generated by a sliding motion of the piston by a damping valve, a part of the oil liquid is introduced to a back pressure chamber provided in a back surface side of the damping valve from a back pressure introduction path, a pressure within the back pressure chamber is leaked from a leak path, and the damping force is adjustable by controlling a valve opening pressure of the damping valve by controlling the pressure in the back pressure chamber, wherein said back pressure introduction path is provided in the piston rod, a leaf valve with a slit is provided at an inlet of said back pressure introduction path, and said slit is formed as an introduction side orifice.