Based on the experimental results by natural rainfall,simulated rainfall and artificially added flushing water,and the analyses of recent increase in the amounts of soil and water loss occurred in the development and construction in the typical area,we found three prediction methods for the development and construction project.They are the mathematical modeling method for evaluation of newly increased soil and water loss,the coefficient method for newly increased soil erosion,and the coefficient method for newly increased soil and water loss.The methods may be used for the prediction of man-made soil and water loss in implementing the development and construction projects in the middle reaches of the Yellow River,and for a reference to other similar area.