The Studies on Quality Assurance Activities at the Phase of Planning - Design Are Quite Rare, While Those Activies are very Important, This Study is Focused on the Applicability of Quality Function Development System to the Phase of Planning-Design, With a Matrix of the Quality Assurance Activities and Quality Function Develop-ment System. The Application of a Quality Function Development System to the Quality Assurance Activities (1) Makes it Easier to Easier out the Quality Level that Consumers Demand and Varies Rapidly, and (2) Makes it Possible to Link the Production to the Quality Level that Consumers Demand by the Quality Specification.