A light emitting diode including a substrate, a p-type and n-type semiconductor layers, an active layer, an interlayer, an electron barrier layer, a first and a second electrodes are provided. The n-type semiconductor layer is disposed on the sapphire substrate. The active layer has an active region with a defect density greater than or equal to 2×107/cm2. The active layer is disposed between the n-type and p-type semiconductor layers. The wavelength of light emitted by the active layer is λ, and 222 nm≦λ≦405 nm. The active layer includes i quantum barrier layers and (i−1) quantum wells, each quantum well is disposed between any two quantum barrier layers, and i≧2. N-type dopant is doped in at least k layers of the i quantum barrier layers, wherein k is a natural number and k≧1, when i even, k≧i/2, and when i is odd, k≧(i−1)/2.