Layered light-emitting diode (LED) of GaN photonic crystal (PC) with periodic air holes is studied. Photonic band structures of the photonic crystal are obtained by plane-wave expansion method. The effects of air-hole radius on band gaps are analyzed, and the results show that the widest band gap is 21.5%. A point dipole polarized in the x-y plane is located in the center of the second GaN layer and is excited by a Gaussian pulse profile for the wavelength of 450 nm. Based on the three-dimensional finite-difference time-domain method, extraction efficiency of the LED is obtained. The effects of the PC thickness and air-hole radius on relative extraction efficiency of layered GaN-LED are analyzed. The results show that the maximum relative extraction efficiency of 2 can be obtained with the optimal structural parameters.