To realize a memory effect in an optical device using the electro wetting effect. An optical device includes: first and second substrates placed opposite each other; a partition provided therebetween; a first electrode provided on one side of the first substrate, at least a part thereof overlapping with a region surrounded by the partition in a plan view; second and third electrodes provided on one side of the second substrate and which are respectively placed opposite the first electrode across the region surrounded by the partition; a smoothing layer provided on one side of the second substrate and which covers the second and third electrodes; and first and second fluid, which are incompatible, disposed in the region surrounded by the partition. The first fluid is made of a liquid body possessing polarity or conductivity, and the second fluid is made of a liquid body containing a liquid-crystalline material.