A portable pressure washer that includes a base and a tank assembly formed as a one-piece structure and for engagement with the base. The tank assembly has a pair of water tanks that are disposed separately from each other and a solution tank that is disposed between the pair of water tanks. Each of the tanks is provided with a filler cap. A latch mechanism is disposed at opposite ends of the base for releasably securing the tank assembly with the base. The base houses a liquid pump and air compressor. A manual selector is mounted at the base and has separately selectable positions for coupling either with the water tanks or the solution tank. A spray hose is coupled from the pump for directing either of the water or solution when the pump is activated.