according to webster and wind (1972) and anderson et al (1987), “organizational buying is a complex process and involves many people from different functional areas, multiple goals and potentially conflicting decision criteria. moreover, the customers of today are also more knowledgeable and selective when making their purchasing decisions. since a key to organizational survival is the retention of customers, companies that want to achieve customer satisfaction must be constantly measuring customer satisfaction and developing effective strategy.” this thesis was designed to identify factors that influence customer satisfaction in business- to- business market, especially in the engineer-to- order (eto) companies in iran and present a model in this special field. also the importances of these factors are examined by customers of nmt, which is one company of the eto in iran. our survey-based field study was conducted among 136 business customers of nmt manufacturer of capital goods industry. the entire statistical problem are solved by spss and lisrel software. finally, three drivers (reliability, product information, commercial aspect), which premised by guatam in 2007, were identified with high correlation between them while these factors could identify by one factor or identify by these three factors but separately . the importance of these factors was not depending on functional area because all of the customers were project managers, but the most important factors were commercial aspects and reliability.