Abstract: The production forecasting about CBM multilateral wells is of guiding significance in many sides such as optimized blocks,economic evaluation and drainage management and so on.Based on dropping pressure char-acteristics about multilateral wells from the multi-branch and the end of the branch in inclining seam in different drilling ways,avoiding complicatedly moving process of CBM from the matrix and cranny,combined with Darcy laws,some models such as dropping of pressure model,desorption radius model and production forecasting model about multi-branch and the end of the branch in two drilling ways along the declining and ascending seams were established.Results showed the preferable applied prospect.