Based on 500 hPa geopotential height from NCEP/NCAR reanalysis data, 500 hPa height forecast obtained from T63L16 model, and Anhui province rainfall data, according to the monthly precipitation anomaly forecast equation, the forecast equation coefficients are calculated by immovable data and selected data from monthly and dekadly time scales, four downscaling methods have been used to forecast Anhui province 20 stations monthly precipitation. Eleven-year hindcast test proves that four methods have good forecasting skill, dekadly scale forecast of monthly precipitation is better than monthly scale, especially in flood season and the year when heavy rainfall happened in flood season.