Abstract: In order to improve regional groundwater development and utilization measures and to aid regional groundwater resource management, groundwater storage variability characteristics were assessed using GRACE data in three provinces of Northeast China from 2002 to 2017. GRACE and GLDAS data were combined to estimate groundwater storage variations. The estimated groundwater storage variations were verified using measured groundwater storage variations and the factors influencing groundwater storage variations were explored. The results showed that the correlation between groundwater storage variations estimated by GRACE and the measured groundwater storage variations was strong, with a correlation coefficient of 0.72. Groundwater storage variations increased significantly at the end of 2011, and the average growth rate was 2.23 mm/a. The largest surplus in groundwater storage was at the end of 2013, and the largest deficit was at the beginning of 2008. There was an evident loss in groundwater storage in the winter and autumn, and an evident surplus in the summer. Furthermore, there were differences in the spatial distribution of groundwater storage. In 2002—2012, there was less groundwater storage in the northeast than in the southwest, and in 2013—2017 there was more groundwater storage in the northeast than in southwest. There were evident groundwater storage variations in Heilongjiang Province. Furthermore, due to drought, there were significant losses in groundwater storage in Liaoning Province and Jilin Province. Groundwater storage variations were strongly correlated with changes in precipitation and had the strongest correlation with agricultural irrigation, with a correlation coefficient of 0.58. In the winter, groundwater storage variations were the most significantly correlated with snowfall, with a correlation coefficient of up to 0.426. By studying the spatiotemporal variability characteristics of groundwater storage in three provinces of Northeast China, this study aims to provide a reference for the optimal allocation of water resources and the sustainable development of the environment in China and globally.