PURPOSE: To provide an oil separator which can efficiently separate oil from a refrigerant gas.

CONSTITUTION: This apparatus contains a first buffer plate 110, a second buffer plate 150 and a stainless filament 120 sandwiched between the first and second buffer plates. The second buffer plate has an induction port 151 for applying a centrifugal force to a refrigerant to discharge a light refrigerant past at the induction port from a refrigerant discharge pipe 160. A separating plate 1 is included having an oil collection port 2 above the oil DO recovered at a lower part of the body 101.