To provide a saddle riding type four-wheel vehicle capable of attaining enhancement of workability of maintenance of an engine or the like.

The saddle riding type four-wheel vehicle is provided with a front side frame part 30 extending in a vertical direction at a front side of the engine and supporting left and right front wheels; a lower side frame part 21 extending from a lower part of the front side frame part 30 to a rear side and supporting a lower part of the engine 11; a rear side frame part 40 extending from the lower side frame part 21 to an upper side behind the engine 11; and an upper side frame part 50 arranged such that at least a part is positioned above the engine 11 and detachable relative to the front side frame part 30 and the rear side frame part 40.