To provide a waste heat power generator exhibiting excellent thermoelectric conversion efficiency.

The waste heat power generator 1 comprises a heat exchanging means (heat exchanging members) 12A for conducting thermal energy of waste gas flowing through an exhaust pipe, a cooling means (cooling sections) 8, and a thermoelectric conversion means (thermoelectric conversion modules) 13 disposed between the heat exchanging means 12 and the cooling means 8 and converting heat energy conducted by the heat exchanging means 12 into electric energy. Rigidity of the cooling means 8 is highest in a system through which heat energy moves, rigidity of the base of the heat exchanging means 12 is highest in an exhaust passage system consisting of a pipe body (divided exhaust pipe body) 5 and the heat exchanging means 12, and the thermoelectric conversion means 13 is secured by pressing the cooling means 8 with a resilient means (spring clamp part) 14 from the outside.