An off-chip large capacitor fast transient response low dropout regulator was designed. The LDO introduced a push-pull structure in the output with the translinear circuit, which effectively reduced the amplitude and recovery time of the overshoot, and improved the transient response speed. The floating buffer was used to drive the power transistor, which effectively improved the LDO’s current efficiency. Dynamic zero compensation technology was adopted to ensure the loop stability of LDO in the all load conditions. The LDO was designed and simulated based on the 0.35 μm BCD process. The results show the input voltage range of the LDO is in 1.2 V~3 V, the output voltage is 1 V, the quiescent current is about 50 μA, and it can provide 0~3 mA load current. During load transients with 500 ns rising and falling edges, 300 mA amplitude, 50 μs light load durations, the overshoot and undershoot are less than 20 mV, which meets the application requirements of high frequency load transition.