A shock absorber includes a cylinder housing including a piston chamber in which oily liquid is disposed, a piston movable in the piston chamber, a rod connected to the piston and protruding out from the cylinder housing, and a return mechanism for the rod. In the shock absorber, a cylindrical bearing made of a synthetic resin having a shock-absorbing property, a dust collecting member for avoiding entry of dust particles, and a lubricating member for supplying a lubricating oil to a surface of the rod are disposed in a rod guiding hole in the cylinder housing. A leading end of the bearing protrudes outside with respect to an outer end surface of the cylinder housing and acts as a contact portion that allows a moving object to come into contact therewith, and thus the bearing functions to guide the rod and also functions as a stopper for avoiding the moving object from coming into contact with the outer end surface of the cylinder housing.