In order to satisfy the quality of product's demand of consumer and improve quality while dropping expend, working procedure must be synthetically controlled because of product of steel-making is a continuous plant composed of many procedures. Logic and physics frame as well as subsystem's functions and interrelations including with quality schedule system, quality data collection system, quality evaluation and control system, quality information management system are analyzed based on CIMS of steel-making plant. At the same time computer aided quality control system of steel-making enterprise is designed and marked out. High grade and low cost products satisfied consumer are yielded by synthetically controlling every working procedure's quality, punctual consignment guaranteed.