Embodiments of the present disclosure disclose a method and device for reducing bandwidth consumption of a display controller. The method includes: whether image data of a current User Interface (UI) frame to be displayed is the same as image data of a previous UI frame is judged; when the image data of the current UI frame to be displayed is the same as the image data of the previous UI frame, image data in a nontransparent region except a transparent region of the previous UI frame is read; and when the image data of the current UI frame to be displayed is different from the image data of the previous UI frame, a transparent region of the current UI frame to be displayed is determined according to a preset strategy. Embodiments of the present disclosure further disclose a display controller and a computer storage medium.