The invention relates to a data driven unit and a drive method thereof. The data driven unit comprises a first switching element, a second switching element and a polarity controller, wherein the first switching element is connected between a drive chip buffer and an output end of a drive chip; the second switching element is serially connected with a delay load and connected between the drive chip buffer and the output end of the drive chip; the polarity controller is connected with the first switching element and the second switching element and controls one of the first switching element and the second switching element to be conductive, while the other one to be broken. The drive method comprises the steps that the polarity controller monitors the polarity of data voltage; when the polarity changes, the polarity controller controls the first switching element to be conductive to ensure that the drive chip buffer and the output end of the drive chip are directly connected; and whenthe polarity is unchanged, the polarity controller controls the second switching element to be conductive to ensure that the drive chip buffer and the output end of the drive chip are connected by thedelay load. The invention reduces the deviation of output waveforms of two rows of grate lines, improves the concealed wire phenomenon and increases the display quality.