The invention provides a gyroscope scale factor testing system and a gyroscope scale factor testing method. The system comprises a mounting device, an acquisition module and a data processing module.By mounting a standard gyroscope and a tested gyroscope on the mounting device and enabling a sensitive axis of the tested gyroscope, a sensitive axis of the standard gyroscope and a rotating shaft ofthe mounting device to be parallel to one another, the acquisition module synchronously acquires an output U1 of the tested gyroscope and the output U0 of the standard gyroscope, and the data processing module calculates a scale factor K1 of the tested gyroscope according to the output U1, the output U0 and a scale factor K0 of the standard gyroscope. The gyroscope scale factor testing system andmethod provided by the invention replace a turntable for testing the scale factor of the gyroscope, have simple operation steps, can simultaneously test the scale factors of a plurality of gyroscopesin one test, save time, reduce cost and facilitate batch production of the gyroscope.