The invention relates to a real-time deformation monitoring pre-warning system based on an inertia-assistance positioning receiver and a real-time deformation monitoring pre-warning method based on the inertia-assistance positioning receiver. The real-time deformation monitoring pre-warning system is characterized by comprising a GNSS (global navigation satellite system) receiver, an accelerometer, a deformation monitoring device including a data interface and a time synchronization module, and a GNSS correction information obtaining device connected with the GNSS receiver and the deformation monitoring device respectively, wherein the data interface is connected with the time synchronization module in sequence, and the GNSS receiver and the accelerometer are connected with the data interface simultaneously. The GNSS receiver outputs the precise positioning result in real time; meanwhile, the accelerometer is adopted to help to capture dynamic deformation signals, the sampling rate stored by data is adjusted reasonably, and the storage space is saved; and due to the arrangement of a buffer area, the high-sampling-rate data of foreboding period of the severe deformation can be stored completely. The system and the method can be widely applied to the monitoring and the pre-warning of the geological disasters such as earthquake, landslide and the like, and applied to the deformation monitoring of dams, bridges, high-rise buildings and the like.