To promote technology integration, it is essential to address pre-service teacher (PST) concerns about facilitating technology-enhanced learning environments. This study adopted the Concerns-Based Adoption Model to investigate PST concern on Web 2.0 integration. Four hundred and eighty-nine PSTs in a teacher education university in north Taiwan participated in this study, achieving a response rate of almost 50%. Participants completed online surveys at their convenience over a two-week period. Significant relationships between the concern and a few personal characteristics were found. The PST concern was most intense in the self-concern stage and then fluctuated from task-concern to impact-concern within a small range. Findings of the study provide valuable insights for personalising teacher education as to how levels of concern, self-efficacy for teaching, teacher knowledge and demographics influence the change process required for Web 2.0 integration in instruction.