In order to meet the aerosol retrieval application requirements of polarized scanning atmospheric corrector (PSAC) over land, the information content and a posterior error analysis is applied to the synthetic data in this paper, which inherits from the optimal estimate theoretical framework. We discussed the angle dependence of the degrees of freedom for signal (DFS) of the aerosol and surface parameters in different scenarios, and analyzed the posterior errors of the aerosol and surface parameters. On this basis, the variation trend of the aerosol and surface parameters DFS with aerosol optical depth (AOD) and surface reflectivity is analyzed. The results show that: 1) Under different observation geometry, the total DFS of aerosol parameters vary greatly, and the optimal scattering angle range of aerosol parameters is ${\mathrm{140}}^{°}～{\mathrm{180}}^{°}$. 2) The columnar aerosol volumes($v_{\mathrm{0}}^{\mathrm{f}}$ and $v_{\mathrm{0}}^{\mathrm{c}}$) for the coarse mode dominated aerosols and the columnar aerosol volumes($v_{\mathrm{0}}^{\mathrm{f}}$) for fine-dominated aerosol models can be inverted at any observation angle, and some parameters of particle size distribution and refractive index can be obtained at large scattering angle. 3) The increase in polarization information is helpful to the inversion of aerosol parameters under the bright surface, and the increase of short-wave infrared band can improve the ability to obtain surface parameters under the condition of high AOD.