The goal of this research and work is to determine the critical thinking competencies of primary school teachers and to what extent they are competent in teaching and developing critical thinking. The study is based on the examination of 8 competencies that are necessary for the successful implementation of critical thinking in education and was conducted on 124 primary education teachers with different years of work experience (0-5; 6-10; 11-20 and >20) with the help of a questionnaire that contained 49 statements and questions. The results of the research are presented and interpreted with regard to the research questions, which are: is there a significant difference in the competence of teachers in teaching critical thinking with regard to years of experience, and how competent primary education teachers are in teaching and developing critical thinking. The analysis of the results leads to the conclusion that teachers with longer working experience are more accomplished in competencies that can only be improved through experience and constant work, while teachers with less working experience achieved better results in skills that are considered imperative in modern society, such as emotional competence and skills in solving problems. Furthermore, the results indicate that younger generations of teachers are more aware of the needs of modern society, while teachers with more experience are certainly more successful in the competencies related to their approach to work and students in general. In conclusion, it was determined that primary education teachers are in most cases prepared and competent for teaching and developing critical thinking in students, and that they are mostly aware of the importance of critical thinking in modern society.