According to the need of teachers who have Internet literacy and can adapt themselves to the age of information, the purpose of this study was to examine the impact of a course of Introduction to Biology Education using internet on the preservice teachers` Internet literacy. In addition, we examined the Internet literacy of the present in-service biology teachers. For this purpose, the course of an Introduction to Biology Education was run with application of Internet services as extra assignments during the spring semester of 1997 academic year. Twenty-nine preservice teachers participated in the course. Pre-questionnaire and post questionnaire results were examined to find out the effect on the Internet ability, the perception, and the Internet attitude of preservice teachers. Similar questionnaire was administered to forty-eight in-service biology teachers. There were a positive influence on the cultivating preservice teachers` Internet literacy through the instructions using Internet, a positive recognition of Internet, and a positive attitude to Internet. Preservice teachers got to have ideas to apply Internet to education. Although most in-service teachers had little experience of using Internet, they admitted the need of the educational application of Internet and showed a positive attitude to learning Internet, which suggested the need of Internet instruction in teacher education.