This study examined whether self-directed learning readiness (SDLR) moderates the association between Internet self-efficacy and approaches to learning by web searching (ALWS). A total of 329 valid questionnaires were used for the correlation and path analysis. The results revealed that preschool teachers' SDLR significantly moderated the influence of Internet self-efficacy and ALWS. Thus, this result suggests that spending more time on SDLR may increase preschool teachers' ALWS, which may enhance their teaching practice via web-based professional development. Findings from this study may have implications for preschool teachers who aim to improve their teaching practice by targeting web-searching environment and approaches to learning. The findings suggest that the positive mediation role of SDLR between Internet self-efficacy and ALWS, especially effective learning, active learning and independent learning of SDLR. Because SDLR has the great influence on the online learning domain, preparing teacher's self-directed learning ability is important for educational authorities to facilitate teachers' better performance when learning online.