To make a differential pressure measuring device less expensive by estimating a temperature of an object to be measured by using a built-in temperature sensor and eliminating the need to arrange another temperature sensor on the outside of the device.

The differential pressure measuring device is provided with a differential pressure capsule section which measures differential pressure values, a pressure sensor which is disposed at the differential pressure capsule section and measures static pressure values, the temperature sensor which is disposed at the differential pressure capsule section and detects the temperature of the differential pressure capsule section, a first temperature estimating circuit which estimates temperature of fluid to be measured from the temperature value measured by the temperature sensor and calculates a temperature estimation value of the fluid to be measured, and a first compensation circuit which carries out both a pressure compensation process and a temperature compensation process for output signals of the differential pressure capsule section, on the basis of signals from the pressure sensor and the first temperature estimating circuit.