An expansion valve according to one embodiment includes a body having a valve hole, a valve element which opens and closes a valve section by moving toward and away from the valve hole, and a shaft one end side of which connects to a drive section and the other end side of which connects to the valve element through the valve hole, the shaft transmitting the drive force, generated by the drive section, to the valve element. Here, the shaft is so provided as to run through an insertion hole formed axially with the valve hole in the body. The insertion hole is formed in the body by a cutting work, and has a support that supports the shaft and a diameter-enlarged part that is open to a downstream side of the valve hole and whose diameter is larger than that of the support.