Basing on the analysis of problems existing in the comprehensive decision-making and balanced optimizing of project programs, the writer has introduced the method of physical planning to solve the problems of comprehensive decision-making and optimizing in the quality of the project management – time limit for a project - cost, and established the quality - time limit for a project- cost comprehensive evaluation and decision model as well as the quality - time limit for a project - cost optimization model. The proposed method has been proved effective through the cases of highway engineering project management.