Abstract: Based on the knowledge and experience of deep excavation engineering, the characteristics of design system for deep excavation were analyzed, namely three dimensions constituted by time, logic with method dimension. Among them, the project design was a key link. From four aspects of safety, economy, environmental protection and construction promptness, the index system for evaluating the project design was established and the optimum decision-making and evaluation model was deduced from the multi-objectives fuzzy decision-making theory for the project design of deep excavation and its application in the actual engineering was proved to gain superior decision result.