Simulating traffic conditions at an uncontrolled median opening, where U-turn movement occurred, has higher complexity than at an intersection due to a lack of vehicle maneuverability at the available width of the road and the median opening and is complicated by disorderly driving behavior and non-compliance with the rule of priority. This condition was simulated using Vissim software to see how accurately Vissim can model it. The research results showed that there were differences in traffic performance, expressed in cumulative through traffic travel time, which is affected by U-turn movement, with the lowest traffic speed of through traffic at the segment when they are waiting for the U-turn process and waiting for the U-turn vehicle merging process. In addition, based on statistical analysis, Vissim is less able to simulate traffic conditions in terms of speed, especially for motorcycles, due to the high disorderly driving behavior of motorcycle drivers in the U-turn area.