The invention aims to provide a hybrid system with improved overall efficiency. A hybrid system according to the present invention is a hybrid system equipped with a fuel cell device and a thermoacoustic cooling machine. The thermoacoustic cooling machine (14) comprises a thermoacoustic energy generation part (20) for generating thermoacoustic energy using a temperature gradient between a high temperature side and a low temperature side, and a cooling part (21) in which the low temperature side has a cooling function which makes use of the temperature gradient between the high temperature side and the low temperature side, which is generated by the energy conversion of the thermoacoustic energy propagating from the thermoacoustic energy generation part (20). The hybrid system is configured such that the exhaust gas discharged from the fuel cell device flows on the high temperature side of the thermoacoustic energy generation part (20). Thereby, it is possible to constitute the hybrid system with improved overall efficiency