Based on the principle of acousto-optic tunable filter and aperture division, the new method that can obtain a high spectral full polarization and image information was proposed. It was improved the accuracy of target detection and object recognition by this method. The Optical system of polarization imaging spectrometer based on aperture divisionandacousto-optic tunable filter was designed in this paper, which was used in the 2.16-meter telescope and spectral range is 450-900 nm.First,the working principle of polarization imaging spectrometer based on aperture division was introduced.Then, the design scheme of optical system and the principle of information acquisition were studied.Finally, the design parameters were assigned and theoptical systems were designed.The whole system MTF reach 0.6 in 32lp/mm.The olarization imaging spectrometer based on aperture division can improve the observation capacity.