The invention discloses a device and method for carrying out parallel processing of scattering net points of light guide plates through femtosecond lasers. The device comprises a light guide plate transmitting and locating device, a light guide plate processing center device, a heat removal and dust removal device, a femtosecond laser holography parallel processing system and a control center. The light guide plate transmitting and locating device comprises a light guide plate transmitting mechanism, an adsorption device and a grating locating sensor. The light guide plate processing center device comprises a complete machine bridge, a supporting plate and ball screw feed devices in the direction X and the direction Y. The femtosecond laser parallel processing system is a beam splitting and conduction device used for emitting a laser beam through a femtosecond laser device and comprises the femtosecond laser device, light path transmitting and controlling equipment, a spatial light modulator (SLM) and a microscope and monitor system. According to the device and method, the liquid crystal spatial light modulator (LCSLM) is utilized for locating a computer generated hologram (CGH), parallel processing of multiple light beams can be achieved at a time, the processing speed can be effectively increased, the processing efficiency is remarkable, the processing time is shortened, and the processing cost is greatly reduced.