A full on chip high precision low power capacitor-less Low Dropout Regulator(LDO) is presented. The circuit realizes high precision by using a high-order curvature compensated bandgap circuit. The power consumption is effectively decreased by using a zero power start-up circuit. In addition, 4 transistors are utilized to enhance slew rate which is good for low power consumption. The circuit was simulated in CSMC 0.5 μm CMOS process. By simulation with Spectre, the circuit achieves an output voltage of 3.3 V, a line regulation less than 0.3 mV/V, a load regulation less than 0.09 mV/mA, a temperature coefficient of 10 ppm/℃ in the temperature range from -40 ℃ to 150 ℃. The total LDO circuit consumes 17.7 μA.