The invention provides a vacuum gauge comprising a cold cathode, a shaded pole, an anode ring and a collector, wherein the cold cathode comprises a cathode emission unit and a grid oppositely arranged with the cathode emission unit; the shaded pole comprises a containing space and two end parts; one end of the shaded pole and the clod cathode are oppositely arranged; the anode ring is arranged in the containing space of the shaded pole; the collector and the other end of the shaded pole are oppositely arranged; the cathode emission unit comprises at least one electronic emitter comprising the tubular structure of a carbon nano tube; the tubular structure of a carbon nano tube is provided with a hollow linear axle center and is formed by that a plurality of carbon nano tubes surround the hollow linear axle center; and the tubular structure of a carbon nano tube is characterized in that a plurality of electronic emission tips extend out of one end of the hollow linear axle center. The vacuum gauge provided by the invention has good sensitivity.