Abstract: In order to meet the need of high precision measurement and control for deep space and high orbit targets, two ionospheric refraction error correction methods based on dual frequency GNSS are proposed, which are space projection method and adaptive mesh method, and the accuracy of ionospheric range refraction error is compared and analyzed when the elevation angle and angle diameter are different. The analysis results indicate that when the correction residual of spatial projection method and adaptive grid method is smaller, and the correction accuracy is better than 0.2 m for 2.0 GHz radio-wave signal with the elevation > 45°. With the decrease of elevation angle or the increase of angle diameter, the correction residual of space projection method increases rapidly, and the correction accuracy decreases to the order of m, while the correction residual of adaptive grid method is hardly affected by elevation angle and angle diameter. The results show that the adaptive grid method has higher correction accuracy, and has stronger applicability for different elevation angles targets, which is more suitable for ionospheric refraction error in engineering.