In order to solve the contradiction between accuracy and radial dimension of an angle sensor, this paper derives and analyzes the axial errors of an end grating and a cylindrical grating from the aspects of radial flux and Moire fringes in detail, and the error model is also established. Based on the axial error analysis, a stereo grating angle sensor combining an end grating with a cylindrical grating is designed and the corresponding experimental system of stereo grating angle sensor is established. The experimental results show that the error of the proposed stereo grating angle sensor is 6.75" when reading head presents a uniform distribution. In contrast, when reading head presents a non-uniform distribution, the error is 4.33".These results provide a new method for the suppression of axial errors and some references for the development of compact and high precision angle sensors.