A drinking fountain for pets has a base with a water receptacle therein and a dome-shaped reserve water tank on the base. A drinking bowl on the top of the tank and a pump system for conveying water in the receptacle to the drinking bowl. Water pumped into the bowl overflows the bowl and flows down over a portion of the surface of the reserve water tank and returns to the receptacle. When the water in the receptacle falls below a predetermined level, water from the reserve tank automatically flow from the tank to the receptacle to increase the water to the prescribed level.