A rotary machine comprising: a rotational driving part; a driving shaft which is rotated by the rotational driving part about an axis that extends in a horizontal direction; a gear wheel which is fixed to the driving shaft; a driving shaft bearing section which rotatably supports the driving shaft and is supplied with lubricating oil; a plurality of pinions which mesh with the gear wheel to be driven; a plurality of compressing parts (11, 12, 13) which are respectively rotated by the pinions; a first plate which is disposed between the driving shaft bearing section and the gear wheel, and covers a region of at least a portion of a lower half of the gear wheel so as to separate the gear wheel from the driving shaft bearing section; a driven shaft bearing section which rotatably supports a driven shaft to which a pinion is fixed; a casing which supports the driving shaft bearing section and the driven shaft bearing section, wherein the casing is provided with an oil groove which guides drain oil, which is discharged from the driven shaft bearing section, toward the gear wheel side; said rotary machine being characterized by comprising a third plate which is independently disposed apart from the first plate between a lower half portion of the driven shaft bearing section and the gear wheel to separate the gear wheel from the driven shaft bearing section; wherein an oil thrower which is constituted by a cut-out ring having a discharge port formed by cutting a lower portion thereof and a cover is attached to each of both sides of the driven shaft bearing in an axial direction so as to allow the drain oil discharged from the driven shaft bearing to be discharged toward a space surrounded by the cut-out ring and the cover, to be discharged toward a lower side from the discharge port in a lower portion of the cut-out ring, and to abut the third plate via the oil groove; and wherein the driven shaft being horizontally spaced from the driving shaft, and as seen in a plane orthogonal to the driven shaft, the plane being divided into four quadrants by the vertical straight line passing through the driven shaft and by the horizontal straight line passing through the driven shaft, the third plate is entirely disposed in the lower quadrant that is closest to the driving shaft. a rotational driving part; a driving shaft which is rotated by the rotational driving part about an axis that extends in a horizontal direction; a gear wheel which is fixed to the driving shaft; a driving shaft bearing section which rotatably supports the driving shaft and is supplied with lubricating oil; a plurality of pinions which mesh with the gear wheel to be driven; a plurality of compressing parts (11, 12, 13) which are respectively rotated by the pinions; a first plate which is disposed between the driving shaft bearing section and the gear wheel, and covers a region of at least a portion of a lower half of the gear wheel so as to separate the gear wheel from the driving shaft bearing section; a driven shaft bearing section which rotatably supports a driven shaft to which a pinion is fixed; a casing which supports the driving shaft bearing section and the driven shaft bearing section, wherein the casing is provided with an oil groove which guides drain oil, which is discharged from the driven shaft bearing section, toward the gear wheel side; said rotary machine being characterized by comprising a third plate which is independently disposed apart from the first plate between a lower half portion of the driven shaft bearing section and the gear wheel to separate the gear wheel from the driven shaft bearing section; wherein an oil thrower which is constituted by a cut-out ring having a discharge port formed by cutting a lower portion thereof and a cover is attached to each of both sides of the driven shaft bearing in an axial direction so as to allow the drain oil discharged from the driven shaft bearing to be discharged toward a space surrounded by the cut-out ring and the cover, to be discharged toward a lower side from the discharge port in a lower portion of the cut-out ring, and to abut the third plate via the oil groove; and wherein the driven shaft being horizontally spaced from the driving shaft, and as seen in a plane orthogonal to the driven shaft, the plane being divided into four quadrants by the vertical straight line passing through the driven shaft and by the horizontal straight line passing through the driven shaft, the third plate is entirely disposed in the lower quadrant that is closest to the driving shaft.