A differential charge pump circuit including a common mode bias unit, a first single-ended charge pump unit, and a second single-ended charge pump unit is provided. The common mode bias unit provides a differential signal to a low pass filter. The first single-ended charge pump unit provides a first current to the common mode bias unit or sinks the first current from the common mode bias unit via the first terminal based on an up signal and a down signal. The second single-ended charge pump unit provides a second current to the common mode bias unit or sinks the second current from the common mode bias unit via the second terminal based on the up signal and the down signal. The first and the second single-ended charge pump units respectively charge or discharge the first and the second terminals of the common mode bias unit.