A microwave photon frequency conversion method is put forward and demonstrated using Mach-Zehnder modulator (MZM) and injection-locked laser.In the upper branch,the laser is modulated by the radio frequency (RF) signal to realize the carrier suppression modulation and then the optical sideband is filtered by the filter;in the lower branch,the laser is modulated by the local oscillator (LO) signal to realize single sideband modulation and then filtered and amplified by the injection-locked laser.After the coupling of the two beams,the light enters the photodetector (PD) beat frequency to realize up and down frequency conversion.The structure makes full use of the feature that the injection-locked laser can be locked by the input laser,and can obtain perfect local oscillator light, so it can generate better microwave signal through the difference frequencies.Simulation results show that the spurious free dynamic range (SFDR) of the system is greater than 90 dB·Hz2/3 and the noise figure (NF) is less than 30 dB.