To provide a small-sized solenoid-driven flow-regulating expansion valve which can be realized at low cost. In a flow-regulating expansion valve according to the present invention, a pipe forming a body thereof not only accommodates internal structures, such as a flow-regulating mechanism, a movable core, and a fixed core, but also serves as a part of piping of a refrigeration cycle. Further, a solenoid section including a solenoid coil is disposed outside the pipe in a manner surrounding the same. Therefore, substantial integration of the flow-regulating mechanism in the piping of the refrigeration cycle can be achieved, which makes the entire flow-regulating expansion valve very simple in construction. As a result, reduction of the size of the flow-regulating expansion valve and resultant reduction of material costs and manufacturing costs can be achieved, which makes it possible to achieve low costs of the flow-regulating expansion valve.