Teacher knowledge guides a teacher's behaviour in the classroom. Teacher knowledge for technology education is generally assumed to play an important role in affecting pupils' learning in technology. There are an abundant number of teacher knowledge models that visualise different domains of teacher knowledge, but clear empirical evidence on how these domains interact is lacking. Insights into the interaction of teacher knowledge domains could be useful for teacher training. In this study, the hypothesised relations between different domains of teacher knowledge for technology education in primary schools were empirically investigated. Subject matter knowledge, pedagogical content knowledge, attitude, and self-efficacy were measured with tests and questionnaires. Results from a path analysis showed that subject matter knowledge is an important prerequisite for both pedagogical content knowledge and self-efficacy. Subsequently, teachers' self-efficacy was found to have a strong influence on teachers' attitude towards technology. Based on the findings in this study, it is recommended that teacher training should first of all focus on the development of teachers' subject matter knowledge and pedagogical content knowledge. This knowledge will positively affect teachers' confidence in teaching and, in turn, their attitude towards the subject. More confidence in technology teaching and a more positive attitude are expected to increase the frequency of technology education, which consequently increases teaching experience and thereby stimulates the development of teachers' pedagogical content knowledge. This circle of positive reinforcement will eventually contribute to the quality of technology education in primary schools.