The present research aimed at improving EFL fourth year student teachers' teaching self-efficacy through Problem Based Learning (PBL). Participants of the research were selected from the fourth year student teachers at Faculty of Education, Benha University, in the academic year 2018/2019. They were randomly assigned into two groups: experimental (n=30) and control (n=30). The instruments of the research were a pre-post scale of teaching self-efficacy (adopted from Hammam's final version, 2016) and a reflection form (prepared by the researcher). The research adopted the pre-post experimental/control group design. Results of the research revealed that the experimental group teaching self-efficacy was significantly higher than the control group. Thus, it is recommended to use PBL in improving teaching self-efficacy at the Faculties of Education in Egypt.