The structure design of GaN-based active-matrix TFT-LED display chip was optimized, and the working principles were introduced in detail. Based on designing the parameters of chip pixel unit TFT transistor, the output current waveform of the LED was simulated with the software of Cadence Virtuoso Spectre Circuit Simulator. Simulation results show that the current going through the LED is 54.86mA, which can provide sufficient breakover current for the chip. It is indicated that the advantages of TFT-LED chip structure are in reducing the peripheral devices while increasing the conduction current.