Abstract: Using the data set of the flow of Heihe river, we have analyzed the persistence, periodicity and annual variation of the flow. It is shown that there is a good positive correlation between the flow of Heihe river in April and surface heating field over the Qinghai-Xizang Plateau in February of the year. The departure characteristics of 500 hPa in March have the predictability to the flow of Heihe river for coming May.