This study aims to analyse the effect of Joyful Learning-based Fiqh learning design on student self-efficacy at MAN Kota Palangka Raya. The research method used a mixed methods approach with a sequential explanatory design, where quantitative data were collected through a self-efficacy questionnaire adapted from Bandura's scale, and qualitative data were obtained through in-depth interviews and classroom observations. The research sample consisted of 60 grade XI students as quantitative respondents and 8 informants (6 students and 2 teachers) for qualitative data. Quantitative data analysis used Product Moment correlation test and paired samples t-test to test the relationship and differences in self-efficacy scores before and after the learning intervention. The results showed a significant increase in students' self-efficacy scores after the implementation of Joyful Learning-based Fiqh learning with a correlation value of r=0.85 and tcount=13.61> ttable=2.00 at the 0.05 significance level. Qualitative data supports quantitative findings by showing that learning methods that are interactive, fun, and support active participation of students are able to increase self-confidence, courage, and motivation to learn. This finding is in line with Bandura's social cognitive theory and Gardner's Multiple Intelligences theory, as well as previous research that emphasizes the importance of a positive and inclusive learning atmosphere in building self-efficacy. In conclusion, Joyful Learning-based Fiqh learning design is effective in increasing students' self-efficacy and can be an innovative alternative in Islamic religious education learning that not only transfers knowledge but also shapes students' character and spiritual confidence as a whole.