To provide a scroll type fluid machine prevented from a lubrication running-out even in starting after a long-term stop.

This scroll type fluid machine has a body housing 1, and a turning scroll 4 and a fixed scroll 5 provided in the body housing 1 so as to be mutually turnable, and feeds lubricating oil stored at the lower part of the body housing 1, into a space between the turning scroll 4 and a thrust bearing part J with which the turning scroll 4 comes in sliding contact and to the sliding contact parts of the turning scroll 4 and fixed scroll 5 and returns excess lubricating oil to the lower part of the body housing 1 through an oil return pipe 22. In this case, the oil return pipe 22 is provided with a shape memory polymer valve 23 for opening the oil return pipe 22 during steady operation and closing a pipeline of the oil return pipe 22 during the stop of operation.