A photolithography process based on photo acid reaction was used to obtain uniform red， green and blue quantum dot films as light-emitting layers， and a high-resolution full-color QLED device （sub-pixel width of 5 μm） was successfully prepared. The device performance of full-color QLEDs was significantly improved by ligand passivation of photolithographic quantum dot surfaces， as well as by introduction of a charge blocking layer to reduce the leakage current in the non-emitting region. The resultant QLEDs showed the maximum brightness of 23 831 cd/m² and external quantum efficiency of 3.87%.