Traffic volume has been increasing rapidly throughout the country, people have a hard time because of the traffic problems especially on the peak hours causing traffic congestion which is the biggest problem in Baghdad city, one of the solutions for congestion is to build an overpasses bridge at intersections in order to minimize these kinds of problems, the research maintains to evaluate the overpass bridge with the help of GIS, the various advantage of GIS makes it an attractive option to be used to face the emerging traffic problems. The main objective of this research is analyzing the existing traffic situation on Al-Yarmouk Overpass Bridge and estimating the level of service via v/c ratios were level of service is one of the constant functions of traffic to either maintain a stable traffic flow or to identify and cure for traffic congestion by gathering information concerning the transportation system in the study area by using field information count, camera for estimating traffic volume, speed Gun device for measuring vehicle speed. The result showed that the overpass bridge operates with the level of service (LOS F), at which the vehicle relative to the road capacity (v/c) is (1.48) as illustrated in analysis map on the basis of analyses of the existing traffics situation of the bridge. Some improvements are suggested to improve the level of service, and optimization suggestion, in addition to geometric improvement, is suggested in this study.