A pixel array module with a self-test function including a test circuit unit, a plurality of test lines, and a pixel array is provided. The test circuit unit provides the self-test function. The test lines are connected between the test circuit unit and the pixel array. The pixel array is connected to the test circuit unit through the test lines and includes a plurality of pixels. Each pixel includes a transistor. Each transistor has a first terminal and a second terminal. Regarding each of the pixels, a driving signal of the transistor is transmitted from the first terminal to the second terminal thereof under a normal mode, and a test signal of the transistor is transmitted from the second terminal to the first terminal thereof under a test mode. Furthermore, a self-test method of the foregoing pixel array module is also provided.