According to one embodiment, a liquid crystal optical element includes a substrate, a first alignment film, a second alignment film opposite to the first alignment film, a spacer between the substrate and the second alignment film, and a liquid crystal layer in contact with the first alignment film and the second alignment film. The liquid crystal layer includes liquid crystal molecules including a plurality of first liquid crystal molecules arranged along a boundary surface with the first alignment film and a plurality of second liquid crystal molecules arranged along a boundary surface with the second alignment film, and is cured in a state where alignment directions of the liquid crystal molecules are fixed.