A shock absorber comprising: a first damping passage (P1, P2) connecting two chambers to each other; a main valve (V1, V2) opening/closing the first damping passage (P1, P2) to give resistance to flow of liquid flowing in the first damping passage (P1, P2); a second damping passage (P3, P4) connecting the two chambers to each other by bypassing the main valve (V1, V2); and a throttle valve (V3, V4) throttling the second damping passage (P3, P4), whereby the throttle valve (V3, V4) includes: a housing including a valve seat provided at one end thereof in an axial direction; a case inserted in the housing to enable a position thereof in the housing in the axial direction to be adjusted; a valve body movably inserted at one end thereof in the case toward the valve seat and restricted from moving to a side of the valve seat in the case; and an elastic member biasing the valve body to the side of the valve seat, characterised in that the valve body includes a head portion opposed to the valve seat, a shaft portion connected to the terminal end of the head portion, and a flange portion extending outward from the outer circumference of the shaft portion, the shaft portion and the flange portion slide in contact with an inner circumferential surface of the case, and the case includes a stopper portion that restricts the movement of the valve body to the side of the valve seat when the shaft portion slides in contact with the inner circumferential surface of the stopper portion. a first damping passage (P1, P2) connecting two chambers to each other; a main valve (V1, V2) opening/closing the first damping passage (P1, P2) to give resistance to flow of liquid flowing in the first damping passage (P1, P2); a second damping passage (P3, P4) connecting the two chambers to each other by bypassing the main valve (V1, V2); and a throttle valve (V3, V4) throttling the second damping passage (P3, P4), whereby the throttle valve (V3, V4) includes: a housing including a valve seat provided at one end thereof in an axial direction; a case inserted in the housing to enable a position thereof in the housing in the axial direction to be adjusted; a valve body movably inserted at one end thereof in the case toward the valve seat and restricted from moving to a side of the valve seat in the case; and an elastic member biasing the valve body to the side of the valve seat, characterised in that the valve body includes a head portion opposed to the valve seat, a shaft portion connected to the terminal end of the head portion, and a flange portion extending outward from the outer circumference of the shaft portion, the shaft portion and the flange portion slide in contact with an inner circumferential surface of the case, and the case includes a stopper portion that restricts the movement of the valve body to the side of the valve seat when the shaft portion slides in contact with the inner circumferential surface of the stopper portion. a housing including a valve seat provided at one end thereof in an axial direction; a case inserted in the housing to enable a position thereof in the housing in the axial direction to be adjusted; a valve body movably inserted at one end thereof in the case toward the valve seat and restricted from moving to a side of the valve seat in the case; and an elastic member biasing the valve body to the side of the valve seat, characterised in that the valve body includes a head portion opposed to the valve seat, a shaft portion connected to the terminal end of the head portion, and a flange portion extending outward from the outer circumference of the shaft portion, the shaft portion and the flange portion slide in contact with an inner circumferential surface of the case, and the case includes a stopper portion that restricts the movement of the valve body to the side of the valve seat when the shaft portion slides in contact with the inner circumferential surface of the stopper portion.