According to one embodiment, a power generation element includes an element part. The element part includes a first conductive member, a second conductive member, and a plurality of first structure bodies provided between the first conductive member and the second conductive member. One of the first structure bodies includes a first portion and a second portion. The first portion is fixed to the first conductive member. The second portion is between the first portion and the second conductive member. A second length along a second direction of the second portion is less than a first length along the second direction of the first portion. The second direction crosses a first direction from the first conductive member toward the second conductive member.