A displaying method for trans-flective type display device is provided. The pixel array of the display device has a selected pixel unit formed by three sub-pixels selected from three basic-color sub-pixels and one enhancement sub-pixel, wherein there is a reflective area within the enhancement sub-pixel. The displaying method includes the following steps. Firstly, an original image having an image data is provided to the display device. Next, when the backlight is turned off, the resolution of the original image is scaled down for obtaining an adjusted image data. Then, another pixel unit consisting of the three basic-color sub-pixels and the enhancement sub-pixel is re-selected, and the driving value of the enhancement sub-pixel is calculated according to the adjusted image data for driving the enhancement sub-pixel.