Abstract: Urban waterlogging and storm runoff pollution become increasingly serious as urbanization is rapidly developing. This paper constructs a regional stormwater model in the frame of SWMM combining a case study of a region located between Xi'an and Xianyang in Shaanxi province, and simulates different rainfall events of the region in traditional development (TD) and low impact development (LID) modes. Results show that: (1) The LID measures are better in alleviating waterllogging at the nodes of the storm sewer system. In this mode, no waterllogging is observed in the rainfall events of short recurrence period, while stormwater runoff and its pollutants can be well controlled in heavy rainfall events. (2) In the conditions of different precipitation, these LID measures can produce an increase of 3.2% - 15.1% in total runoff control rates and a delay of 5 - 30 minutes in flood peak time. Comparing with TD mode, the LID reduction rates in total loads of suspended solids, chemical oxygen demand, total phosphorus, and total nitrogen are increased by 28.2% - 38.9%, 25.2% - 36.3%, 29.8% - 40.0%, and 26.6% - 37.3% respectively. The LID measures can effectively regulate urban storm runoff and reduce pollutant loads. However, with the increasing return period of design rainfalls, their runoff regulating and load reducing effects are gradually decreasing.