The present invention discloses an LED and its fabrication method. The LED comprises: a substrate; an epitaxial layer, an active layer and a capping layer arranged on the substrate in sequence; wherein a plurality of microlens structures arc formed on the surface of the substrate away from the epitaxial layer, and a plurality of cams are formed on the surfaces of the microlens structures. When the light emitted from the active layer passes through the surfaces of the microlens structures or the surfaces of the cams, the incident angle is always smaller than the critical angle of total reflection, thus preventing total reflection and making sure that most of the light pass through the surfaces of the microlens structures and the cams, in this way improving external quantum efficiency of the LED, avoiding the rise of the internal temperature of the LED and improving the performance of the LED.