Abstract: The portable sink includes a main case having an open top and a hinged cover. In place in the main case is an inside case and a sink bowl unit. A supply tank is removably fitted in the inside case. The supply tank is generally closed, but having a filling opening and openings for conduits for admitting compressed air thereto and explusion of water therefrom. In response to placing the supply tank in the inside case, connections are automatically made for controlling a flow of air from a supply of compressed air into the tank. The sink bowl unit has two bowls, one of which is higher than the other, enabling water to run from the higher one to the lower one, and an outlet is provided in the lower sink bowl into a waste tank which is detachably secured in the assembly. A hose is connected to the outlet of the tank to enable the user to direct the water expelled from the tank into the sink bowl, or to other points of use.