The aims of this study are to evaluate the the right-turn coefficients at intersection capasity formula by Indonesia Highway Capacity Manual (MKJI 1997). Therefore, it is necessary for analysis that examines right-turn coefficient values in intersection capacity function. The simulation with many various geometric intersections defined by many scenarios using vehicle tracking application program, which increase the space maneuver vehicle at the intersection includes: 1) widen approach lane; 2) add a right-turn lane; and 3) backward median in each approach. Intersection performance Analysis will produce degree of saturation that is affected by right-turn coefficient according to the simulated vehicle maneuver using new formula. The study can be concluded that the intersection changes the right-turn factor adjustment which was originally set with the value based on linear function being a log function. According to the new function, Prt Less 2,5% right turn vehicle make significant decrease of intersection capacity, that why, it makes many conflict based on opposite traffic from other approach. In the other side, if Prt more then 2,5%, it makes increase intersection capacity because intersection space used to right turn vehicles.