Fluid machine, and waste heat-utilizing system for automobile using same

A waste heat-utilizing system for an automobile, wherein a fluid machine is configured so that a compressor (24) for a refrigeration cycle (20) and a pump (46) and an expander (48) for a Rankine cycle (40) are disposed on coaxial rotating shafts (25) in such a manner that the compressor, the pump, and the expander are sequentially integrated in this order. A transmission means (26) which operates in association with the rotating shaft (7) of an internal combustion engine (2) is provided to the end of the rotating shafts which is located on the compressor side.