Digital manufacturing(DM) is the ability to describe every aspect of the design-to-manufacture process digitally-using tools that include digital design, CAD, office documents, PLM(Product Life-cycle Management) systems, analysis software, simulation, CAM software and so on. The major automotive companies are already deeply invested in DM with almost every process being digital rather than paper-based. But it has taken a long time for the digital process to mature into something usable and there have been some major barriers that have prevented from the DM becoming a reality. Thus many companies hesitate to make a decision of implementing the DM. This paper deals with a study investigating which factors are important for implementing the DM to industries successfully. The extended technology acceptance model (ETAM) is used as the relation model of cause and effect. The quality of hardware, the quality of software, the range of collaboration among companies and the preference of the user are defined as the external factors. Interview method is used for gathering input data, and the results are analyzed with SPSS. The results indicate that four external factors are effective on the successful implementation of DM, and the perceived usefulness is most important.