There are increasing opportunities for learners and instructors in different education level to engage in Internet-based or Internet assisted learning and instruction; therefore, it is important to explore pre-service and in-service preschool teachers' Internet attitudes and Internet self-efficacy. This paper explores 1210 Taiwanese preschool teachers, including 673 pre-service teachers and 537 in-service teachers' Internet attitudes and Internet selfefficacy. Internet Attitude Scale (IAS) and Internet Selfefficacy Scale (ISS) were conducted to assess preschool teachers' attitudes and their self-efficacy toward the Internet. Exploratory factor analyses indicated adequate reliability and validity of the two questionnaires. Results of this study were shown that in-service teachers' scores in perceived usefulness of Internet were significantly higher than the pre-service teachers' scores. However, pre-service teachers' scores in affection toward Internet were significantly higher than in-service teachers' scores. Moreover, the regression analyses revealed that preschool teachers' general selfefficacy can positively predict their Internet attitude of perceived usefulness, perceived control and behavior, and their communicative self-efficacy can positively predict their Internet attitude of perceived control and behavior. However, the preschool teachers' status (i.e. pre-service and in-service) was negatively predicting the Internet attitude of affection and behavior. As the results, the in-service preschool teachers would be more likely to be fill with anxiety when using the Internet and less frequently to use Internet.