When the traditional pixel patterning process for the OLED-on-Si microdisplay fabricates the pixel anodes in two independent process flows,the anode patterning process based on complementary metal oxide semiconductor(CMOS) process is presented to simplify the manufacture process flow and reduce the huge investment cost.The electro-optical performance of the organic light emitting microdisplay with Al serving as the pixel anode material in the general CMOS process is analyzed.A Si chip for the microdisplay backplane with the minimum pixel size of 12 mm×4 mm is developed.The organic lighting material is produced on the silicon chip surface to fabricate the OLED-on-Si microdisplay.The experiment results show that the light intensity is more than 1 000 cd/m2 and the current density is more than 0.1 mA/mm2 when Al is used as the pixel anode material and the 5 V voltage is applied to drive the OLED pixel.The electro-optical response is less than 280 ns.These results indicate that it is feasible to develop the OLED-on-Si microdisplay in the conventional CMOS process.