Provided are a mechanical quantity measurement device having a higher signal-to-noise ratio and resolution than the prior art and a pressure sensor using the same. A mechanical quantity measurement device that is provided with a plurality of Wheatstone bridges on the main surface of a single semiconductor substrate that are composed from impurity-diffused resistors and detect the difference between the strain amount occurring in the x-axis direction and the strain amount occurring in the y-axis direction, which intersect at right angles on the main surface of the semiconductor substrate, said mechanical quantity measurement device being characterized in that the impurity-diffused resistors composing the plurality of Wheatstone bridges are disposed evenly in an area to be measured.