A gallium-nitride(GaN) based light emitting diode (LED) structure utilizing materials having compatible lattice constant is provided. When aluminum-indium-nitride (AlxIn1-xN, 0<x<1) is used to make the p-type cladding layer within the GaN-based LED structure, the cladding layer has a lattice constant compatible with that of GaN. The active layer's multi-quantum well (MQW) structure, therefore, would not be damaged from the excessive stress resulted from the incompatible lattice constant during the GaN-based LED's epitaxial growth. In addition, AlxIn1-xN (0<x<1) has a wider band gap than that of GaN, which can prevent electrons from overflowing from the MQW active layer. This, in turn, will increase the possibility of forming electron-hole pairs within the MQW active layer. Also due to its wider band gap, AlxIn1-xN (0<x<1) has an effective confinement effect on the photons, which again will increase the GaN-based LED's lighting efficiency. Besides, AlxIn1-xN (0<x<1) has a lower growing temperature so that the MQW active layer would remain intact during the low-temperature growth of the cladding layer, which, again, would increase the GaN-based LED's lighting efficiency.