The mixer is one of the basic components of all receivers (RX), but testing the group delay and phase using network analyzer is not easy and there is little research on microwave field on the measure of mixer. It is too difficult to screen microwave devices at domestic then the article mainly focuses on testing techniques for microwave mixers. The testing circuit of microwave mixer and testing methods of the parameters of microware are described in the paper. Microwave mixer is one of the key parts in Satellite Navigation system. So it is worth to research the measure technology of mixer further.