For simplicity, we only compare purchase cost of LED Lights and electricity bills, but actually the neglected factors are also important in commercial lighting area. As for commercial lighting where lights are used for eight hours, the LED light sources are of economic efficiency at the price of 11.23 yuan. While at the occasion of light use for four hours, economic efficiency occurs at the price of 7.76 yuan. Currently the prices of light sources are all lower than these, which mean LED definitely has economic efficiency in commercial lighting. The light source of led high bay has efficiency two times higher than that of traditional light source. The usage time is 250 days annually with the electricity price 0.8 yuan per kilowatt hour, and the discount rate is 15%.