The learning model known as the flipped classroom is one of the developing ideas of educating students. Bergmann and Sams (2012) using a flipped classroom in 2007 when they recorded lecture for students to view at home and allowing students to work on “homework” in the classroom. This research was conducted to identify the effect of the flipped classroom on student self-efficacy and the difference in self-efficacy between genders using this model. This study was conducted with 22 physics students in two classes, a traditional and a flipped classroom. The student’s self-efficacy was scored with the Self-Efficacy Survey. The results showed an increase in their average self-efficacy score with the flipped classroom while the traditional classroom decreased their average score. When analyzed separately, the males showed a decrease in self-efficacy while the females showed an increase while using the flipped classroom.