The invention discloses a rotating speed monitoring device adopting a photoelectric counting technology for a wind power generator. The rotating speed monitoring device structurally comprises rotatingblades, a rotating circular ring, a photoelectric rotating speed device, an angle adjusting device, a rotating motor and a protective shell, wherein one ends of the rotating blades are embedded intothe interior of the rotating circular ring, and the other ends of the rotating blades are attached to the inner surface of the protective shell. According to the rotating speed monitoring device adopting the photoelectric counting technology for the wind power generator, the forward and reverse rotation of the rotating motor is realized by controlling a power control device, power is transmitted through a braking mechanism and a transmission mechanism so that an upper rotating mechanism and a lower rotating mechanism can be controlled, finally, rotating angles can be adjusted through an angleadjusting plate, and therefore the rotating speed state of the wind power generator in the natural environment can be monitored from different directions through the rotating angles, the monitoring efficiency is improved, and the application range of the device is expanded.