In an apparatus for controlling a starting clutch of a vehicle having a function of stopping engine idling so that an engine is automatically stopped under given conditions when the vehicle is at a standstill, the starting clutch being disposed in a transmission of the vehicle in series with a belt type continuously variable transmission mechanism which receives an input of a power from the engine through a power transmission mechanism having built therein hydraulically operated frictional engaging elements, the vehicle start-up from the state of engine stopping is made smoothly at a good response. At the time of vehicle start-up from the state of engine stopping, when the rotational speed of the drive pulley of the transmission mechanism has increased to a predetermined speed, the control mode of the starting clutch is switched from the waiting mode in which the engaging force of the starting clutch is kept below a creeping force which causes the vehicle to creep, to a running mode in which the engaging force of the starting clutch is increased above the creeping force.