New online group-buying websites of the recent rise such as Groupon, GOMAJI and 17Life are very popular, because they often can offer more discounts. Product sales capability of the new online group-buying websites is better than other websites by 2011. In this paper, we want to find the successful product sales strategy of the new group-buying website by the product sales model analyses. According to transaction records of Groupon Online, the product sales model is constructed using product category, product prices, product discounts and product source. This research, we will find different sales patterns by product sales capability. Then the product sales model is verified by Artificial Neural Network. Back-propagation neural network was applied to forecast capability. Finally, we provide selling strategy suggestion to the new products.