This paper studied about effects of the certificate of ISO 9000 in the manufacturing companies whose number of employee is under three hundred. First, most of company answered that acquiring the certificate of ISO 9000 is very helpful for the company management. therefore the company has the competence in the change of domestic and international economy. Second, after acquiring the certificate of ISO 9000, there were many improvements in company culture, quality control and business process productivity. As a result, the acquisition of the certificate of ISO 9000 system makes the company culture preparing the future to become a world first class company.