We report on the characteristics of high-power near-ultraviolet flip-chip InGaN light-emitting diodes (LEDs) fabricated onto a patterned sapphire substrate (PSS). When the PSS flip-chip LED (chip size: 1 mm × 1 mm) operated at a forward current 20 mA at room temperature, the forward voltage and the light output power were measured to be 3.15 V and 6.8 mW, respectively. Moreover, the light output power was greatly increased by 59% for the PSS flip-chip LED sample at a forward injection current of 350 mA. This result was attributed to increase in probability of escaping photons from the LEDs sample, resulting in the enhancement of light extraction efficiency.