A thermoelectric conversion element includes a thermoelectric conversion sheet possessing flexibility. The thermoelectric conversion sheet includes a magnetic layer, an electricity-generating layer that is formed on the magnetic layer so as to contact with the magnetic layer and that is formed of a material exhibiting spin orbit coupling, and a first electrode and a second electrode formed on the electricity-generating layer so as to contact with the electricity-generating layer. The first electrode and the second electrode extend in a longitudinal direction of the thermoelectric conversion sheet, and are separated from each other in a first direction perpendicular to the longitudinal direction.