A power generation device comprising: a frame including a through hole to pass therethrough in a first direction and form an inner surface; a duct disposed in the through hole of the frame and having a flow path such that a first fluid flows in a second direction perpendicular to the first direction; a first thermoelectric module including a first thermoelectric device disposed on a first surface of the duct and a first heat dissipation fin disposed on the first thermoelectric device; a second thermoelectric module including a second thermoelectric device disposed on a second surface opposite to the first surface of the duct and a second heat dissipation fin disposed on the second thermoelectric device; characterized in that a plurality of tilting members is disposed in the inner surface of the through hole along the second direction on the duct and faced to each other; and a guide member disposed on a third surface disposed between the first surface and the second surface of the duct , wherein the first surface and the second surface face each other along a third direction perpendicular to the first direction and the second direction, wherein a second fluid passes through the through hole along the first direction, wherein the guide member extends along the second direction between the plurality of tilting members , wherein each of the plurality of tilting members and the guide member includes a tilting surface, wherein a tilting direction of the tilting surface of the guide member is different from a tilting direction of each tilting surface of the plurality of tilting members , wherein the tilting surface of the guide member is tilted so that the second fluid branches and flows along the first direction, wherein a separation distance between the tilting surfaces of the plurality of tilting members is greater than or equal to a length of the guide member along the second direction. a frame including a through hole to pass therethrough in a first direction and form an inner surface; a duct disposed in the through hole of the frame and having a flow path such that a first fluid flows in a second direction perpendicular to the first direction; a first thermoelectric module including a first thermoelectric device disposed on a first surface of the duct and a first heat dissipation fin disposed on the first thermoelectric device; a second thermoelectric module including a second thermoelectric device disposed on a second surface opposite to the first surface of the duct and a second heat dissipation fin disposed on the second thermoelectric device; characterized in that a plurality of tilting members is disposed in the inner surface of the through hole along the second direction on the duct and faced to each other; and a guide member disposed on a third surface disposed between the first surface and the second surface of the duct , wherein the first surface and the second surface face each other along a third direction perpendicular to the first direction and the second direction, wherein a second fluid passes through the through hole along the first direction, wherein the guide member extends along the second direction between the plurality of tilting members , wherein each of the plurality of tilting members and the guide member includes a tilting surface, wherein a tilting direction of the tilting surface of the guide member is different from a tilting direction of each tilting surface of the plurality of tilting members , wherein the tilting surface of the guide member is tilted so that the second fluid branches and flows along the first direction, wherein a separation distance between the tilting surfaces of the plurality of tilting members is greater than or equal to a length of the guide member along the second direction. <EOS>