(57) A limit switch comprising a case (1) housing a switching unit (2), a head (3) secured to one end of the case, a rotary shaft (4) rotatably supported by the head and having a flat portion (14), a manipulation lever (7) secured at a butt end thereof to the rotary shaft which supports at a tip (7B) end thereof roller (8) means for detecting an object, a return coil spring (16) provided in the head which applies a force through a return plunger (15) to the flat portion of the rotary shaft to return the manipulation lever to a free position, a disk cam (19) secured to the rotary shaft and having a projection (30) formed on a peripheral portion thereof in a position corresponding to the free position of the manipulation lever, manipulation plunger means for the switching unit which is driven in response to rotary movement of disk cam and elastic stopper means (31) disposed in the head for contacting the projection of disk cam and for braking the manipulation lever when manipulation lever is returned to the free position, whereby the lever is prevented from being swung back beyond the free position. Therefore, the switching unit is prevented from chattering.