To provide a manufacturing method of a heat sensitive rate flow sensor which can suppress the contact of a tip end of a part formed in a storage recessed portion suppressing the excessive swivel of detected fluid in a recessed portion, with a sensor tip.

A sensor chip 10; and a mounting member 20 formed with a storage recessed portion 21 mounting a sensor chip 10 on one surface 20a, and formed with a through-hole 23 on a bottom surface of the storage recessed portion 21 are prepared. Then, the recessed portion 12 and the through-hole 23 are opposed, and a part of the sensor chip 10 is mounted on the bottom surface of the storage recessed portion 21 through a connecting member 70. Resin is injected from the through-hole 23, and a protrusion portion 22 extending from the bottom surface of the storage recessed portion 21 in a direction of the sensor chip 10, disposed in the recessed portion 12, and separated from the sensor chip 10 is formed.