A vehicle generation controlling system for saving fuel includes a battery supplying power to electric components of a vehicle, a generator generating power by using rotational force of an engine and supplying the generated power to the battery and the electric components, and an ECU determining whether generation control is prevented by monitoring vehicle information on the vehicle and operational information on an operation of an electric product of a cooling system among the electric components and controlling the generator to prevent the generation control according to the determination. As a result, the generation control is performed based on whether an electric product of a cooling system is actuated and vehicle information on the vehicle to thereby prevent cooling performance from being deteriorated due to the generation control.