Abstract: This paper presents a problem-solving strategy, called as propose-and-revise strategy, used in VT expert system. The strategy proposes trially a extended plan first, revises it by means of domain knowledge when it violates the constraint of the whole to it. This strategy has the advantages of decision with optimization and high efficiency and organization of domain knowledge partition. It is universally applicable to problem-solving systems for derign, configuration, planning and so on.