A method for displaying error rates of data channels of a display is provided. A timing controller of the display repeatedly transmits a test signal with a specific format to a first and a second source drivers of the display via a first and a second data channels of the display. During testing, a first number and a second number of times of the first source driver and the second source driver determining that the received test signal does not have the specific format are counted respectively. The first and the second source drivers control displaying of a first area and a second area of a panel of the display respectively according to the counted first and second numbers of times. Accordingly, the error rates of the data channels are presented on the panel of the display in a way that the error rates could be recognized more easily.