The invention relates to a refrigeration compressor having a sealed housing defining a suction volume and a compression volume respectively provided on either side of a body (5) contained in the housing, and an oil injection circuit adapted for injecting oil into the compression volume. The oil injection circuit includes a stopper (26) mobile under the action of a centrifugal force between a first position for injecting oil into the compression volume and a second position preventing or limiting the injection of oil into the compression volume, wherein the stopper (26) is adapted so as to move into the second position when the speed of the compressor exceeds a predetermined value.