A thermoelectric conversion module in which a plurality of P-type thermoelectric conversion elements and N-type thermoelectric conversion elements, which are combined in pairs, are connected in series between a pair of opposing wiring substrates via the wiring substrates: electrode parts to which the thermoelectric conversion elements are connected, are formed on surfaces of ceramic substrates of the wiring substrates: among the thermoelectric conversion elements, the thermoelectric conversion element having a larger thermal expansion coefficient has the length, in a direction in which the wiring substrates face each other, that is smaller than the length, in a direction in which the wiring substrates face each other, of the thermoelectric conversion element having a smaller thermal expansion coefficient: an electrically conductive spacer is interposed between at least one of the two ends of the thermoelectric conversion element having a larger thermal expansion coefficient and the ceramic substrate of the wiring substrate.