The invention provides a pierce point-based regional augmentation system real-time ionosphere modeling method. The method includes the following steps that: a base station network solution model is established, so that dual-frequency carrier phase ambiguity is obtained; a double-difference mode to non-difference mode ionosphere delay decomposition model is established based on the dual-frequency carrier phase ambiguity; and a pierce point deployed vertical ionosphere delay inter-station model is established, a set of model parameters with a master station adopted as a center is obtained. According to the pierce point-based regional augmentation system real-time ionosphere modeling method of the invention, double-difference ionosphere delay is decomposed to non-difference ionosphere delay; the relevance model of observation stations is built at a pierce point of a satellite and observation station sight line and the thin layer of the ionosphere, so that a set of model parameters in a whole area with the master station adopted as the center can be obtained; the correction number of the ionosphere can be calculated according to the position of a virtual reference station (VRS); and the correction number of the ionosphere is sent to a user through a double-difference mode converted from the non-difference ionosphere delay. The theoretical model of the algorithm is more rigorous than that of an existing algorithm. With the algorithm of the invention adopted, the problem of large interpolation error when the ionosphere is active can be solved to a certain extent.