In order to quantitatively analyze the response characteristics of ground surface deformation to groundwater level in Tianjin, the ground surface deformation monitoring data was obtained through small baseline subset interferometric synthetic aperture radar (SBASInSAR) technology. The seasonal decomposition algorithm was applied to decompose the signal of ground surface deformation and groundwater level data 2018 to 2022. On this basis, the relative importance of each component of the groundwater level to the ground surface deformation was calculated by random forest algorithm, and the response of each component of the ground surface deformation to the groundwater level was analyzed by using dynamic time warping (DTW), cross wavelet transform and Copula function analysis , respectively. The results show that the surface deformation in Tianjin has basically formed five subsidence funnels in the southwest, central and eastern regions of Tianjin. The relative importance of the groundwater level trend component, seasonal component, and residual components to the comprehensive characteristics of surface deformation were 0.595, 0.172, and 0.233, respectively. The similarity between the surface deformation and the trend component of the groundwater level is relatively high, with a comprehensive DTW distance of 10.59. A dominant resonance period of approximately 1 year was identified between the seasonal components of surface deformation and groundwater level, with a lag time of 93 to 132 days for surface deformation relative to seasonal groundwater fluctuations. The joint distribution probability was not less than 0.75 when the probability value of the marginal cumulative distribution function of surface deformation and the residual component of groundwater level were both set to 0.8, indicating that there was a strong correlation between the two.