Group purchase is a shopping mode that customers buying goods which been selling at a discount in a limited period of time and specific website. Nowadays, facing the large number of application of commodity. Group purchase website as a Platform, which has to intervene a lot of manpower for product review. Also may excessively dependent on the former experience. This paper intends to use the decision tree algorithm to analyse the sales volume of the group purchase goods. Generate readable decision tree to make a strategic decision and select the high quality goods.