A cylinder head cover structure of a vehicle which can shorten a longitudinal length of a vehicle while avoiding the restriction on the layout of an engine. A motorcycle includes a vehicle body frame, an engine which is mounted on the vehicle body frame in a suspended manner and includes a cylinder head cover and a radiator which is arranged in front of the engine and behind a front wheel. A recessed portion which is recessed toward a rear side of the vehicle is formed in the cylinder head cover so as to allow a lower portion of the radiator to enter the recessed portion.