The aim of our research is to develop a reliable and valid Hungarian version of the Norwegian Teacher Self-Efficacy Scale – NTSES for measuring teacher self-efficacy, which is suitable for measuring Hungarian teachers in Slovakia, and to examine teacher self-efficacy among teachers in Slovak primary schools with Hungarian as the language of instruction. A total of 160 primary school teacher participated in the survey, which was representative for the examined region. We created a new model using factor analysis – NTSES-H3. We were able to identify three well-interpretable factors (Behaviour Management, Pedagogical Methods, Coping). The statistical analyses examined the reliability indices of the new model of NTSES, which range from 0.744 to 0.834 (Cronbach’s alpha). Significant differences were found depending on the settlements, age/generations, place of graduation, school organization and the size of the institution. Differences in the level of self-efficacy were also caused by whether there is a teacher in the family, what pedagogical degree the teacher has and what pedagogical classification the teacher works in. The linear regression model showed that several factors are not influenced by pedagogical practice, but by age itself. Teachers in the lower grades feel more effective in all the sub-domains studied. Teachers’ self-efficacy also differed depending on the university they had studied at. Overall, the teachers who completed our questionnaire felt most effective in the application of pedagogical methods, followed by behaviour management, and the last to be considered in terms of their coping abilities was their belief in themselves.