[Problems] To provide a thermoelectric power generation system that has a relatively simple configuration, is not prone to failure, and is capable of efficiently generating power from temperature changes in the surrounding environment alone, even where there is no heat source.
[SOLUTION] A thermoelectric power generation device 13 is arranged between a heat storage body 11 having a phase-change material 11b and a heat exchange body 12 whose heat dissipation rate and/or heat absorption rate is greater than that of the heat storage body 11. The thermoelectric power generation device 13 is configured to generate electricity from the temperature difference between the heat storage body 11 and the heat exchange body 12. The thermoelectric power generation device 13 is plate-shaped, and one surface may be in contact with the heat storage body 11 and the other surface may be in contact with the heat exchange body 12.