This study aimed to investigate the effect of geometric characteristics and traffic scenarios on the performance measures, including delay, volume to capacity (v/c) ratio, capacity, and the level of service (LOS) in basic and rotor turbo roundabouts. In addition, it attempted to compare turbo roundabouts using performance measures based on geometric characteristics and traffic scenarios. The results showed that performance measures reduced significantly by increasing the diameter of four-leg turbo roundabouts although they improved in three-leg turbo roundabouts. Further, four- and three-leg basic turbo roundabouts had a better performance by changing the balanced to imbalanced traffic flow scenario compared with four- and three-leg rotor turbo roundabouts. Additionally, substituting four- and three-leg basic turbo roundabouts for rotor four- and three-leg turbo roundabouts increased the performance measures. Overall, the basic turbo roundabouts had a better performance compared to the rotor turbo roundabout under unsaturated and saturated traffic conditions .