Self-efficacy is one of the important soft skills for students because it affects success in solving a problem. This study aims to: (1) describe the self-efficacy of Mathematics Education students in the differential calculus course; (2) analyze the effect of the self-efficacy of Mathematics Education students on learning outcomes in the differential calculus course. This research is a survey research with a descriptive quantitative approach. In taking the sample, the researcher used a purposive sampling technique, namely class C differential calculus with a sample of 22 students. The instruments used in this study were test questions and self-efficacy questionnaires. The results showed that in general students self-efficacy was in the moderate category, with details of 18% in the high category (H), 59% in the medium category (M), and 23% in the low category (L). In addition, self-efficacy has a positive effect on student learning outcomes by 57.3%.