A cylinder with a shock absorbing function which can detect a position of a piston rod reciprocating in a cylinder tube and has a function of absorbing shock produced by the piston rod at its stroke end includes: a pair of piston valve sheets provided in a piston unit; a piston valve configured to reciprocate within a range between the piston valve sheets; a slider made of a nonmagnetic material slidably fitted onto the piston rod; a valve piston provided in the piston unit; a magnet holder ring attached to the piston rod so as to be positioned between the piston unit and the slider; and a magnetism detector provided on an outer periphery of the cylinder tube and configured to detect a position of the piston rod by detecting magnetism generated by the magnet.