An oil supply apparatus for a vehicle may include an oil pump, a first rotary member provided to the oil pump such that the oil pump may be rotatably operated by the first rotary member, a second rotary member restricted from rotating with respect to the first rotary member in a first direction, the second rotary member being allowed to rotate with respect to the first rotary member in a second direction opposite to the first direction, and a third rotary member allowed to rotate in the first direction with respect to the first rotary member, the third rotary member being restricted from rotating with respect to the first rotary member in the second direction opposite to the first direction, wherein the second rotary member and the third rotary member may be respectively connected to power sources providing drive forces in directions opposite to each other.