Taking Qingjiang River Shuibuya upstream basin as research object,the paper extracted terrain characteristics information by use of DEM data, and used DEM based distributed hydrological model to simulate the rainfall-runoff processes in this basin.The application effect of distributed hydrological model is not ideal in hydrological forecast for the lack of dada and the imperfect theory. So the paper set up self regression model to correct the simulation result of rainfall and runoff,and compared with that of uncorrected result in terms of Nash-Sutcliffe coefficient of efficiency and the relative errors of total runoff amount.The conclusion showed that autoregression model can correct error of flood forecast result of DDRM effectively, and compensate make up the degradation of forecast accuracy of distributed hydrological model for the lack of data to a certain extent.