Abstract: A cooling lubricant replenishing device for a compressor has an adapter, a flexible tube, a three-way tube, a pressure gauge, and a check valve. The adapter is adapted to selectively mount on a refrigerant inlet of the compressor and communicate with three-way tube via the flexible tube. The three-way tube has three ends respectively connected with the flexible tube, the pressure gauge, and the check valve. The check valve adapts to further connect with an extruder containing cooling lubricant, the extruder provides a pushing force to make the cooling lubricant pass through the tubes and enter the compressor. Whereby, the compressor is conveniently replenished with the cooling lubricant by using the extruder in a convenient way.