Provided is a modified hydrocarbon resin that provides a hot melt adhesive composition with low odor, excellent heat stability, and high adhesive properties. The modified hydrocarbon resin is obtained by hydrogenating a hydrocarbon resin comprising a plurality of specific monomeric unit in a specific range, and characterized in that: a degree of hydrogenation of the olefins, a degree of hydrogenation of the aromatic rings, a weight average molecular weight (Mw), a Z-average molecular weight (Mz), a ratio (Mz/Mw) of the Z-average molecular weight to the weight-average molecular weight, a Gardner color scale of a toluene solution of 50 mass %, and a difference between pre-hydrogenation and post-hydrogenation mixed aniline point (MMAP) are within the specific range.