To provide a cowl structure for a vehicle for improving the appearance of the vehicle without increasing the weight of the vehicle and also for enhancing the operational stability. In a cowl structure for a vehicle which includes a front cowl for covering a front portion of a vehicle body, a radiator is positioned in front of the cylinder heads of the engine. A radiator cover is provided for covering the radiator ranging from side surfaces to a lower end of the radiator. Bulging portions are provided for bulging from a front portion to a rear portion of the radiator cover and being formed in a direction to be rearwardly and upwardly oblique in a side view of the vehicle. The bulging portions are formed on a lower end portion of the radiator cover.