There is provided a four-cycle engine which can appropriately circulate oil in an engine regardless of a tilted condition with a simple structure. A crankcase (4) of a four-cycle engine (1) has a crank room (41) which rotatably supports a crankshaft (10) and an oil room (42) which is provided adjacent to the exterior of the crank room (41). The crankcase (4) also has partition walls (43) and (44) which partition the interior of the crankcase (4) into the crank room (41) and the oil room (42), respectively, and a communication path (45) which communicates the crank room (41) with the oil room (42). The partition walls (43) and (44) each has a cross section formed in a substantially V shape, and the communication path (45) is formed at an apex between the partition walls (43) and (44).
