The causes of soil and water loss in opencast coal mine are analyzed based on No.1 coal mine of Shengli diggings in Inner Mongolia.The cells and periods of soil and water loss forecast are classified.The contents and means adopted for the project are introduced.The degree and quantity of soil and water loss are found.The harm of soil and water loss in opencast coal mine are illuminated by analyzing the results, and a base for the following measures is established.