Abstract: The method of atmospheric precipitable water vapor based on PPP and the 3D ionospheric tomography method based on pixel base are studied. Combined with Chongqing CORS and IGS real-time service product (RTS), a regional water vapor ionospheric monitoring platform is constructed. The platform can provide high spatial and temporal resolution water vapor 2D, ionospheric 2D and 3D products in real time, and now web is released online. The platform extends the service field of CORS in Chongqing, which is of great significance for monitoring short-term abrupt weather phenomena and studying fine morphological changes of the ionosphere.