A three-dimensional display including a display and a micro-lens is provided. The display has a plurality of pixel units thereon, and each pixel unit has a pixel pitch i. The micro-lens is disposed at a side of the display, the micro-lens has a plurality of lens units thereon, and each lens unit has a lens pitch l. A right eye viewing zone and a left eye viewing zone are formed if an image displayed from the display passes though the micro-lens, wherein a distance between the center of the right eye viewing zone and the center of the left eye viewing zone is wz, and lens pitch l satisfies: 2 ⁢ i > l ≥ 2 ⁢ i × w z w z + i , wz is between 70 and 500 mm and i is between 0.1 and 500 μm.