Abstract: The key influencing factors on traffic flow capacity at modern tram level crossing are analyzed, including non-motorized traffic, lane number at level crossing, signal phase control and number of running trams. Based on this, the parking line method is used to establish a traffic flow capacity model at tram level crossing in 3 conditions: no signal priority, relative signal priority and absolute signal priority. Taking the Xingang East intersection on Guangzhou modern tram test section as an example, the average headway time interval is calculated based on a traffic survey, and the traffic flow passing abilities in conditions of fixed signal control and absolute signal priority are obtained according to the traffic flow capacity model. The research results provide a guidance for the planning, design and management of trams, and will improve the efficiency of road network operation.