A diaphragm-type pressure gauge which is attached to a vessel to be measured and measures a pressure by introducing a gas inside the vessel includes a housing into which the gas is introduced, and a sensor unit which is arranged in the housing, and includes a diaphragm electrode, a measurement surface of which is arranged parallel to an introduction direction of the gas. When the housing is attached to the vessel, the measurement surface of the diaphragm electrode is arranged parallel to a direction of gravitational force.