Provided is a shock absorber which facilitates an insertion/fixation operation. The shock absorber includes a spring-force application unit (84) for applying a force in a valve-closing direction to the disc valve while allowing the fixed shaft to be inserted through the spring-force application units (53) to (58); and a cylindrical member (47) for allowing the fixed shaft (21) to be inserted therethrough, the cylindrical member being inserted into each of the valve discs (53) to (58) and the spring-force application unit (84), in which: the cylindrical member (47) is provided so as to have a radially extending gap on an inner side of the inner seat (31) of the valve main body (14).