Vehicle Ad Hoc Networks (VANETs) refers to an open mobile Ad hoc network composed of communication between vehicles, between vehicles and fixed access points, and between vehicles and pedestrians in a traffic environment. The key factor for its safe operation is real-time accurate location information. The information is often provided by the global navigation satellite system, but some defects of the system limit its applications in the urban area, such as low accuracy or failure under signal occlusion. This study proposes a positioning algorithm based on vehicle-to-everything (V2X) communication. It combines the information obtained from the connected vehicle-to-infrastructure(V2I) or vehicle-to-vehicle (V2V) node and the one that is provided by the on-board inertial navigation system and sensing system to estimate the positions of the target vehicle. The simulation results show that this algorithm performs well in some simulated urban driving scenarios. Its accuracy and stability can meet the strict requirements of most positioning applications.