The purpose of this paper was to find out whether students' reading self-efficacy can be enhanced by using Internet-based extensive reading materials. A pretest-posttest control group design was employed. A sample of 60 intermediate EFL learners from an Institute in Boukan, West Azerbaijan, Iran was selected randomly and their level of reading self-efficacy was measured through Seeger's Self-Efficacy Scale in Reading (2009). In addition, a preliminary test of proficiency was conducted. For a period of two months, the experimental group was supplied with stories through a weblog designed by the researcher, whereas the control group was provided with the same stories printed on paper. The experimental group was connected to the Internet, while the control group was instructed as traditional reading classes are. After the treatment, the learners' level of self-efficacy was again measured with the same scale as in the pre-treatment. Results of the Paired and Independent samples t-tests revealed a significant difference in the reading self-efficacy of both groups, with a higher increase for the experimental group. Discussion and pedagogical implications will also be presented.