To provide an optical element capable of further widening the range of variable focal distance.

An optical element 10 includes a liquid lens that is formed by sealing a first liquid 20 and a second liquid 19, which does not mix with the first liquid 20, in a container 12 and capable of changing the shape of a boundary surface 21 between the first liquid 20 and second liquid 19 by changing a voltage (physical quantity) applied to the inside of the container 12. The optical element 10 has: half prisms 16 which are located on the first liquid 20 side and through which the optical axis X of the liquid lens passes so as to pass through the boundary surface between the first and second liquids 20 and 19; and an optical member 17 located on the second liquid 19 side and through which the optical axis X of the liquid lens passes so as to pass through the boundary surface between the first and second liquids 20 and 19. The half prisms 16 are provided with a selective light ray transmission/reflection face 16a.