In this study, the first gridded hydroclimate dataset in eastern China (EC) during the last millennium was generated. This hydroclimate dataset mainly consisted of two components. The first section was created by interpolating drought/flood grades from 1500 to 2000 using the angular distance weight method. Sampling error estimates were employed to assess the effects of the interpolated dataset. The second section for the hydroclimate dataset during 960-1500 was generated by constructing best subset regression models using selected tree-ring chronologies in the United States/northwestern China through atmospheric teleconnection. The validation parameters of the calibration equations were also derived, including the adjusted R2, predicted R2, RE, and CE. This dataset includes three files named Hydr_EC.mat (43KB), Val_Par.mat (4KB), and SEE.mat (1KB), respectively. In detail, Hydro-EC is the hydroclimate in eastern China during the last millennium; Val-Par and SEE are the dataset’s validation results.