A lens includes a first substrate, a second substrate and a medium layer. The first substrate includes a first electrode layer, an insulation layer, a second electrode layer and a first alignment layer. The first electrode layer includes first electrodes, and the second electrode layer includes second electrodes formed on the insulation layer. The second electrodes separately overlap the first electrodes, and one of the second electrodes shifts relatively to the corresponding first electrode toward a first direction. The first alignment layer is formed on the second electrode layer and has a first rubbing direction opposite to the first direction. The liquid crystal layer is disposed between the first substrate and the second substrate. A three-dimensional display is also disclosed herein.