A transmission apparatus includes a casing provided with shafts therein, a rotational member positioned in the casing at an end portion in an axial direction of the shafts, the rotational member being configured to lift up a lubricating oil so as to supply the lubricating oil to a part that is different from the end portion inside the casing, and an oil passage provided along the axis line direction of the shafts, the oil passage configured to receive the lubricating oil lifted up by the rotational member at a first end portion in a longitudinal direction of the oil passage and to supply the lubricating oil through a second end portion in the longitudinal direction of the oil passage to a part inside the casing placed far away from the rotational member, the oil passage being integrally formed with the casing.