An optical element includes a light entry surface configured to receive light, a light emission surface having a first light emission sub-surface and a second light emission sub-surface connected to each other, and a reflecting surface having a first reflecting sub-surface and a second reflecting sub-surface connected between the first reflecting sub-surface and the second light emission sub-surface. A first portion of the light is transmitted to the light entry surface and the first light emission sub-surface in sequence. A second portion of the light is transmitted to the light entry surface, the second reflecting sub-surface, and the second light exit sub-surface in sequence. A third portion of the light is transmitted to the light entry surface, the first reflecting sub-surface, the second reflecting sub-surface, and the second light emission sub-surface in sequence.