Abstract: A system for collecting used oil from an engine. The system includes a collector vessel, a drain pan which can be releasably mounted on the collector vessel, and a threaded sealing cap. For draining the oil, the collector vessel with the drain pan mounted thereon is placed below the drain plug of the engine. The drain pan includes a top wall in the form of a downward sloping recess having an outlet at its lowest point and a side wall at the periphery of the drain pan. The used motor oil is emptied into the drain pan and flows down the recess to the outlet into a communicating entrance mouth of the vessel. After the used oil has been drained from the engine, the drain pan is removed from the collector vessel and the threaded cap is used to seal the vessel's entrance mouth. The vessel also includes a handle for facilitating the transport of the vessel to a location for disposal of the used oil.