Abstract: A speed controller is capable of being applied to a cylinder with a short stroke with a simple structure. The speed controller includes a first flow channel and a second flow channel allowing a first port and a second port to communicate with each other, into which pressure fluid is allowed to flow, in which a first valve is arranged in the first flow channel, a second valve is arranged in the second flow channel, a third flow channel and a fourth flow channel are further included, and a third valve is arranged in the third flow channel, allowing only flowing from the first port toward a portion on the piston shaft side with respect to a piston in a cylinder chamber in the third flow channel as well as closing the first flow channel and the fourth flow channel by moving a third valve body in a direction of opening the third flow channel, and opening the first flow channel and the fourth flow channel by moving the third valve body in a direction of closing the third flow channel.