OIL FILTER ATTACHING STRUCTURE FOR VEHICLE-MOUNTED INTERNAL COMBUSTION ENGINE An oil filter attaching structure for a vehicle-mounted internal combustion engine, in which the internal combustion engine (3) has an oil filter (8) installed in a filter case (80) integrally formed with a crankcase cover (60R) of a crankcase (30), wherein: said crankcase cover (60R) is mounted on a side surface of said crankcase (30) so as to cover an end (31a) of a crankshaft (31) supported by said crankcase (30) so as to extend in vehicle widthwise directions; an internal combustion engine accessory (47) and a clutch device (50) of an engine transmission are disposed inside of said crankcase cover (60R) in respective positions forward and rearward of said crankshaft (31); and said oil filter (8) and an oil supply port (49) are disposed in said crankcase cover (60R) in respective positions upward and downward of said crankshaft (31). CNCo -o-
