A low dropout regulator is provided. The low dropout regulator includes a first gain-stage, a second gain-stage, an output setting stage, and a Miller circuit. The first gain-stage generates a signal at a first gain-stage terminal based on a signal at a second gain-stage signal. The second gain-stage receives the signal at the first gain-stage terminal and generates a signal at a sensing terminal. The output setting stage outputs a load current to an output terminal. The signal at the sensing terminal is changed with the load current. The Miller circuit is electrically connected to the first gain-stage, the second gain-stage, and the output setting stage. The Miller circuit provides a capacitance related to a dominant pole of the low dropout regulator. The capacitance is changed with the signal at the sensing terminal.