The invention relates to a cam limit switch, which comprises a shell, a driving wheel component arranged in the shell, a worm wheel adjusting component and a contact switch component, and is characterized in that the driving wheel component comprises a first drive-ratio gear component, a second drive-ratio gear component and a third drive-ratio gear component which use driving shafts, driving wheels, planet gears and rotating cams as structural units; the worm wheel adjusting component comprises a worm, a worm wheel, a planet gear meshed with the worm wheel and a rotating cam driven by the planet gear; and the rotating cam of the driving wheel component and an inching switch of the switch component are in movable contact to connect or disconnect an electrified circuit. The cam limit switch solves the problem that the prior cam limit switch has single drive ratio. The cams drive respective inching switch to perform signal transmission, can perform remote control of high-voltage electrical equipment, and are safe and reliable. The cam limit switch also adjusts the positions of the cams conveniently and is simple to maintain.