In order to use the phase change material Ge2Se2Sb4Te1(GSST) to improve the performance of the optical switch, this paper designs an on-chip multifunctional controllable infrared optical switch based on the phase change material. The device is filled with a phase change material GSST in an ultra-compact silicon waveguide with an etched nanohole array structure. By adjusting the characteristics of the phase change material, it can realize the control of signal light in different polarization states in the infrared band. The simulation results show that the light with a wavelength of 1750~1880 nm, when the GSST material is crystalline, the polarization extinction ratio of TE mode light is as high as -30.7 dB, while the insertion loss of TM mode light is only -5.39 dB, when GSST phase change material in an amorphous state, the insertion loss of both can be ignored.