Proposes a novel digital watermark solution for the color image of screen stream based on the spatial domain and the DCT domain. It embeds visible watermark into the spatial domain adaptively, and also embeds invisible watermark encrypted by chaotic sequence into the DCT domain to achieve protected screen color image with dual digital watermark embedded. The effectiveness and good results of this method in multimedia courseware have been testified that the visible watermark is frail to be suitable for copyright notification and the invisible watermark has good robustness for copyright protection.