In recent years, more and more attention has been paid to the detection technology of optical element surface defects. The surface quality of optical element will directly affect the performance of optical system. The detection of micro-defects on the surface of spherical and cylindrical optical elements in curved optical elements are studied, and a detection method based on optical polarization characteristics is proposed. The contrast of defects in the whole image is improved by using the difference of the polarization state of transmitted light between the defect area and the non-defect area. Firstly, based on the polarization theory of light, polarizer is used to obtain polarized illumination light, and confocal illumination is used to obtain the defect image of curved optical element focusing at the same time. Then, using computer to process the defective image. The results show that high contrast and high resolution defect features can be obtained by using polarization characteristics of light to detect micro-defects on the surface of curved optical elements. This method is very good to improve the accuracy and detection efficiency of micro-defects on the surface of curved optical components, and the results show that the detection accuracy of defects reaches 95%.