Aim/Purpose: Flipped learning, in which students engage with instructional content before class and participate in active learning during class time, has emerged as an innovative teaching approach. While previous research has explored various aspects of flipped learning, its impact on student self-efficacy across different contexts remains understudied. Background: This systematic review addressed two key research questions: (1) How does the flipped classroom approach affect students' self-efficacy? and (2) Does this effect vary by subject domain and student age? Methodology: Following PRISMA guidelines, we analyzed 44 peer-reviewed articles (published between 2015 and 2024) from four major databases, encompassing 5,434 participants across 17 countries. Contribution: This review uniquely contributes to the field by providing the first comprehensive analysis of the impact of flipped learning on self-efficacy across different educational contexts and age groups. Findings: The review revealed that flipped classrooms significantly enhanced self-efficacy across all age groups, from K-12 to adult learners, with particularly strong effects in traditionally challenging subjects like mathematics and science. Quantitative analysis showed that 41 out of 44 (93%) studies reported positive effects on student self-efficacy, while only 3 showed no significant impact. Unlike previous research suggesting the effectiveness of flipped learning was limited to technical subjects, our findings demonstrate its broader applicability across diverse disciplines, including language learning and arts education. The study identified key success factors, including pre-class video accessibility (reported by 85% of studies) and interactive in-class activities (implemented in 91% of studies). However, technical infrastructure challenges and increased teacher preparation time emerged as primary implementation barriers. Recommendations for Practitioners: These findings have important practical implications for educational institutions considering flipped learning implementation, suggesting the need for robust technical support systems and professional development resources for teachers. Impact on Society: This review demonstrates that flipped learning represents a powerful tool for enhancing student self-efficacy across diverse educational contexts, but its effectiveness depends heavily on thoughtful implementation and adequate support structures. Future Research: Future research could examine the optimal duration and intensity of flipped learning interventions and investigate how different types of pre-class content affect student self-efficacy outcomes.