the financial perspective, the customer perspective, the process perspective, the innovation and learning perspectives. the case study is done in five gas treating companies with different ages of quality systems registration. the results indicate the following important points: the first, the Balanced Scorecard successfully used to measure the performance of quality systems in studied companies. Second, the productivity of the internal process is increased as well after establishing this quality system; and the third, the innovation and learning perspective in somehow is neglected in these companies. Meanwhile it can be concluded that investments in quality systems increase oranizational performance