A gas flow type angular velocity sensor comprising two semiconductor substrates with all components formed thereon by use of semiconductor technology and IC technology, which are coupled with each other to form therein a pair of heat wires, a gas path and a nozzle hole for injecting a gas flow toward the paired heat wires in the gas path. Two heat wires of the pair change their resistance-temperature characteristics in accordance with a deflection of the gas flow due to the action of angular velocity and a difference between two changed values is picked up and amplified by a resistance bridge circuit and an amplifier circuit formed on the semiconductor substrates to produce an output signal proportional to the angular velocity to be measured. A miniature pump formed on semiconductor substrates and drivable by a piezoelectric element provides a stabilized gas flow in the sensor. As thus constructed the sensor is compact, accurate and suitable for mass-production and free from disadvantages of conventional sensors.