Polarization aberration will affect the accuracy of polarization measurement and the polarization imaging effect of an off-axis optical imaging system, and thus it is necessary to calibrate and compensate for it. On the basis of three-dimensional polarization ray tracing, this study analyzes the polarization aberration of the coded super-resolution off-axis optical imaging system with a digital micro-mirror device (DMD) in different fields of view and proposes a method of polarization compensation by adding a linear attenuator (LD) and a linear retarder (LR) in the optical path near DMD. The calculations indicate that the maximum diattenuation and the maximum phase retardance introduced by the DMD surface are 1.43×10^-3 and 9.52×10^-3 rad, respectively, while the maximum diattenuation and the maximum phase retardance introduced by the overall optical system are 2.32×10^-3 and 1.55×10^-2 rad, respectively. Hence, the polarization aberration introduced by DMD accounts for more than 60% of that introduced by the whole system. Then, this paper compares the polarization aberration distributions, Jones pupils, and polarization imaging simulations of the overall optical system before and after polarization compensation. The results reveal that after an appropriate weak polarizer is used for compensation, the diattenuation and phase retardance are reduced by about a half, with the Jones matrix close to the unit matrix and the crosstalk phenomenon in polarization imaging alleviated significantly. It can be concluded that DMD introduces severe polarization aberration, but the utilization of the LD and LR in the optical path near DMD can simply and effectively compensate for the polarization.