The research on power system planning, scheduling and control often relies on the power data of each power station supply in the system. When the power system is actually running, it is difficult for each plant station to operate under a unified time base, resulting in time series of multi-source output power data do not match. Aiming at the problem of multi-source data point mismatch, this paper proposes a multi-source data fusion method based on multi-source data time point matching. Firstly, the reference time series is determined, and the expressions of each power output power time series relative to the reference time series are established. Secondly, determine the time series common domain of each power output, and construct a multi-source output power point matching model. finally, correct the time series of each power output according to the model solution result, and fuse each power output data. The example analysis shows that the method can accurately integrate the power data of power system, which is of great significance for the research of power system planning, scheduling and control.