Vehicular Ad hoc Networks (VANET) assumes a significant job in future vehicle to vehicle correspondence frameworks and related applications such as self- sorting out traffic data framework. Congestion control for VANETs is extremely useful for VANET network performance and applications.A state happening in system when the message traffic is heavy to the point that it hinders organize reaction time.Congestion control is a difficult issue inside VANETs (vehicular ad hoc networks). Vehicular ad hoc networks (VANET) are a type of MANETs utilized for correspondence among vehicles and among vehicles and roadside gear. VANET carry new difficulties to accomplish safe correspondence engineering inside such condition.