This study, which was conducted to examine the relationship between the self-efficacy perceptions of teachers working in vocational and technical high schools and their perceptions of 21st century skills towards school principals, was carried out on the basis of the exploratory sequential mixed design, which is one of the mixed research designs. In the quantitative dimension of the study, 610 teachers working in MTL located in K.Maraş province were included by criterion sampling method. The qualitative study group consists of 24 teachers selected by purposive sampling method. In the study, data were collected using the "Educational Manager 21st Century Skills Scale", "21st Century Skills Self-Efficacy Perception Scale" and an interview form. The data obtained from the scales were tested by t-test, ANOVA test and correlation analysis. Qualitative data were analyzed by descriptive analysis method. Based on the research findings, the following conclusions were reached; While a significant difference was found in both scales according to both gender and seniority, no significant difference was found according to graduation status. In the analysis of qualitative findings, teachers' opinions supporting these findings were frequently encountered. As a result of the correlation analysis, a positive and significant relationship was found between both scales. In the sub-dimensions of the scales, it was observed that there were generally positive and significant relationships.