A portable steam sterilizer for surgical and dental instruments includes an outer casing and a pressure chamber configured to receive steam therein. A tray is configured to hold the instruments and is releasably received within the pressure chamber while a boiler is in fluid communication with the pressure chamber for providing steam thereto. The sterilizer further includes a container for receiving condensed steam evacuated from the pressure chamber. The container is spaced from the outer casing and includes a main body and a lid that is substantially non-rotationally coupled to the main body. A conduit is coupled to the lid and fluid communicates the container with the pressure chamber. The main body of the container may include a base while the lid may include a wall oriented generally orthogonal to the base.