Display device and image display method

The invention discloses a display device and an image display method. The display device includes a display unit having N adjustable screen resolutions; a storage unit storing a setting list, the setting list recording the N adjustable screen resolutions and N display ratio parameters; a processing unit retrieving a current screen resolution from the display unit and comparing the current screen resolution with the N adjustable screen resolutions, the processing unit selecting an i-th display ratio parameter corresponding to an i-th adjustable screen resolution from the N display ratio parameters when the current screen resolution is identical to the i-th adjustable screen resolution; and an image generating unit generating an image according to the i-th display ratio parameter and displaying the image in the display unit.