Wavelength switching of all-polarization-maintaining Er-doped mode-locked fiber laser based on graphene saturable absorber is reported.Based on multi-layer graphene saturable absorber mirror,stable mode-locked fiber laser can be obtained,and cavity loss can be modulated by tuning the mirror in three-dimensional orientation,which can control the gain and loss of laser with different wavelengths.The experimental results show that wavelength switching at center of 1532 nm and 1560 nm can be realized by adjusting graphene saturable absorber mirror,and dual-wavelength mode-locked laser can be obtained in short cavity.Extinction ratio of output laser can be up to 18 dB.