Cylindrical vector beams(CVBs) are spatially non-uniform polarization distributions. It has been widely used in microscopic imaging, particle manipulation, beam shaping, and other fields. Accurate measurement of the CVBs polarization state distribution is one of the research problems. In order to analyze the influence of systematic errors on the CVBs polarization parameters, the measurement errors of the polarization azimuthal AOP under annular sampling are investigated in this paper. Firstly, the generation of CVBs and the measurement principle of Stokes parametric method is introduced; secondly, the radial and angular vector beam intensity images and the AOP distribution under different annular sampling are simulated; then, the variation of R=256 intensity error IΔ with the polarization azimuth error θ in the range of [-2°,2°] is analyzed. Finally, the single error and the coupling error are analyzed and discussed. The simulation results show that the intensity errors IΔ1 and IΔ2 are the same with the θ, and IΔ3 and IΔ4 are the same with the θ. Under the single error, the absolute error values of the AOPs with mutual residual angles are similar. The maximum absolute error of AOP of IΔ1 and IΔ2 is 1° (@45°) and the maximum relative error is 2.59% (@30°); the maximum absolute error of AOP of IΔ3 and IΔ4 is 1°(@0°) and the maximum relative error is 5.12% (@15°). Under the coupling error, the absolute AOP error of IΔ1 and IΔ2 increases with the increase θ, with the maximum value of 2° (@45°) and the maximum relative error of 5.25% (@30°); the absolute AOP error of IΔ3 and IΔ4 decreases with the increase of θ, with the maximum value of 2°(@0°), with a relative maximum error of 10.40% (@15°). The study provides an error data reference for CVBs polarization detection. It can provide technical support for the application of CVBs in different fields. © 2023 SPIE.