The invention discloses a ground surface three-dimensional deformation monitoring method based on InSAR and GPS data fusion, which comprises the following steps: 1, distributing GPS points; 2, collecting GPS signals and collecting SAR images; 3, resolving GPS points; 4, inhabiting SAR image spot noise; 5, establishing the coordinate conversion relationship between the GPS and SAR data; 6, utilizing GPS data for modifying SAR satellite trajectory errors; 7, forming an InSAR differential interference map; 8, utilizing GPS points for inverting the atmospheric delay; 9, modifying the InSAR atmospheric delay errors; 10, unwrapping the InSAR differential interference map; 11, converting the unwrapping phase into deformation information; 12, carrying out geographical coding on the InSAR deformation information; 13, fusing InSAR and GPS deformation information to obtain high-precision ground surface three-dimensional deformation results; and 14, utilizing the Kalman wave filter estimation andobtaining the ground surface three-dimensional deformation results with high spatial resolution. Because the invention adopts the ground surface three-dimensional deformation monitoring technology with the fused InSAR and GPS data, the application limitation of the single monitoring technology can be broken through, and the spatial resolution of the ground surface three-dimensional deformation monitoring results is greatly improved. The monitoring precision, particularly the precision in the vertical direction is high, and at the same time, the integral reliability of the system is enhanced.