The valve body of a gas torch is provided with a combined preheat oxygen and cutting oxygen valve unit in which the respective valves are coaxially interengaged and mounted in a single bore provided therefor in the valve body. The preheat oxygen valve is rotatable relative to the bore to control the flow of preheat oxygen to the torch tip, and the cutting oxygen valve is axially displaceable relative to the preheat oxygen valve to control the flow of cutting oxygen to the torch tip. The preheat oxygen valve includes an operating knob by which the valve is rotated and which knob is disposed beneath a pivotal operating lever by which the cutting oxygen valve is operated.