The dataset is China's monthly potential evapotranspiration, with a spatial resolution of 0.0083333 ° (about 1km), a time range of 1990.1-2021.12, and a unit of 0.1mm. This data set is based on China's 1km monthly average temperature, minimum temperature and maximum temperature data set (released, Peng at al. 2019), which is obtained by using Hargreaves potential evapotranspiration formula (Peng at al. 2017) and will be updated continuously. For the convenience of storage, the data are all int16 type and stored in nc (NETCDF) files. NC data can be drawn with ArcMAP software; Matlab software can be used for extraction. Related literature link https://doi.org/10.5194/essd-11-1931-2019 ， https://doi.org/10.1016/j.agrformet.2016.11.129 。