The reasons of the luminous efficiency of InGaN-based high-voltage light-emitting diode (HV-LED) better than that of traditional high power (THP) LED are researched and analyzed from three different aspects. The experimental sample with same chip size, material and package structure is adopted to ensure the reliability of experiment conclusions. Experiments show that the luminous efficiency of HV-LED is better than that of THP LED for uniformer current distribution and the light from the microchip gap. The results show that the luminous efficiency of HV-LED is approximately 4.5% higher than that of THP-LED under 1 W input power.