This study investigated Internet adoption using the Technology Acceptance Model (TAM). Research from the 1990s on information technology acceptance was reviewed in the literature, and based on this, the causal relationships among Internet adoption factors were tested. As external factors affecting Internet adoption, individual-related variables (usage experience) and organization-related variables (organizational support) had a greater influence than task-related variables (task ambiguity, task interdependence). Ease of use and usefulness had a positive effect on Internet usage, while subjective norms had a negative effect, and self-efficacy did not show a significant effect. The implications and limitations of these results were discussed in the conclusion.