Abstract: In order to avoid the conventional interpolation model unrelated with observations and improve the accuracy of network RTK atmosphere error interpolation,a new model suitable for atmosphere error estimation with large height difference is given based on atmosphere mapping function and conventional interpolation model,whose variables are satellite elevation,reference station height and distance respectively.Finally,different interpolation models are used to process observations of part reference stations of Jiangsu CORS for estimating atmosphere error.The results by comparison and analysis show that the new model will increase the accuracy of atmosphere error estimation effectively.One hand,mapping function estimation method and lower-order surface model can accurately estimate the double difference troposphere error between users and main reference station with less than 2cm in maximum mean square error.On the other hand,mapping function estimation method,lower-order surface model and linear interpolation method are equivalent in accuracy for double difference ionosphere estimation,but the accuracy of distance interpolation method is the worst with nearly 5 cm error.