Vehicle power transmission device

A vehicle power transmission device comprising:

• a differential mechanism including a differential case rotatably disposed around a rotation axis and provided with a through-hole in an outer circumferential surface, a pair of pinion gears respectively fitted to both ends of a pinion shaft fixed to the differential case, and a pair of side gears rotatably supported by the differential case and meshed with the pinion gears;
• and
• a baffle plate that includes an oil passage component functioning as an oil passage for supplying a lubricating oil for lubricating the pinion gears and the side gears and that is fixedly disposed to cover an outer circumference of the differential case, wherein
• the oil passage component is provided with an opening portion allowing the lubricating oil in the oil passage to flow out downward, and wherein
• the opening portion is disposed above the pinion shaft and between a pair of inner-circumferential-side end surfaces of the pair of the pinion gears when the pinion shaft is horizontal.