Objectives Hydrological loading has an important influence on crustal movement observation network of China (CMONOC) coordinate time series, and rainfall directly affects the magnitude of hydrological loading.

Methods We use CMONOC coordinate time series under the international terrestrial reference frame 2014 (ITRF2014), MERRA2 (modern-era retrospective analysis for research and applications, version 2) model and the rainfall data in China to analyze the relationship among them.

Results The results show that the impact of hydrological loading on the CMONOC stations is mainly reflected in the vertical direction. Especially in the Pearl River Basin and the south, southwest and southeast of the Yangtze River Basin, the hydrological loading has a significant influence on the displacement of the stations. The maximum root mean square value of the hydrological loading series can reach 5.47 mm. Both hydrological loading and rainfall show relatively obvious latitude correlation. The higher the latitude, the smaller of the magnitude of hydrological loading and rainfall, and the goodness of fit with R² can reach 0.63 and 0.55, respectively. At the same time, the rainfall and hydrological loading also show an obvious linear relationship, with R² reaching 0.49. If the average annual rainfall increases, the magnitude of hydrological loading also increases. For periodic signals, the rainfall, hydrological loading and CMONOC coordinate time series are consistent. The annual amplitude of hydrological loading and CMONOC coordinate time series with the annual average rainfall all show a relatively obvious linear relationship, and R² reach 0.64 and 0.37, respectively.

Conclusions In the study of the influence of hydrological loading on global navigation satellite system coordinate time series, in addition to soil moisture, snow cover and canopy water, rainfall is also a part of the reasons that need to be discussed.