Electric Power Research Institute of Guangdong Power Grid Corporation, Guangzhou 510062, China

In order to monitor the changes of water resources in Southwest China in the past year, the GRACE-FO gravity satellite data and GLDAS hydrological model data were used to study the spatial and temporal changes of land water, surface water and groundwater reserves in the region, in combination with precipitation data. The results indicate that ① land water and surface water show obvious seasonal changes, which appear as upward trend in summer and autumn but downward trend in spring and winter;② the land water and groundwater in Southwest China declined from June 2018 to September 2019,and their annual trends are (-1.87±0.82) cm/a and (-2.15±0.96) cm/a, respectively;③ precipitation is the main reason of seasonal change of land water and surface water, and also the main cause of Yunnan drought in 2019.