近年來，寫作能力越來越受重視。然而文章立意主旨為文章之核心，更是一篇成功文章的重要關鍵。群體合作在學習以及寫作上，皆能帶來正面的助益，因此，本研究之目的在於提供一方法，透過群體合作模式，並以數位化系統呈現，期望不僅能降低學生產生立意主旨之負擔，亦能提升立意主旨之創意性。 以完整的系統開發來看，本研究仍屬前導階段；本研究以訪談與使用者意見調查進行形成性評量，將獲得更廣泛之意見做為日後改進方向。經過訪談12位大專學生，從訪談問卷中反映的意見來看，學生對於本研究的評價皆屬正向，認為本研究對於降低學生在寫作立意主旨上的負擔是有幫助的，並且在創意度部分也有一定的提升。 ;Writing is an ability to convey ours viewpoints and feelings through words to convince the reader of our opinion. It’s one of the most essential skills now. Nowadays, writing become more and more important even it will be a subject in the comprehensive assessment program for junior high school students in the future. How, the main idea is not only the core of the article, but the key of a good article. Collaborative Learning and collaborative writing can help student a lot in writing, so our goal is to provide a digital collaborative writing system to reduce the burden on constructing the main idea and enhance their creativity. We conduct a formative evaluation on our system through questionnaire survey and interview with 12 university students. According to the result, our system is effective. It indeed can reduce the burden on constructing the main idea and enhance students’ creativity. In conclusion, the students have positive response to system and we hope development more comprehensive in the future.