Connectedness to nature should be developed from an early age because it is a significant part of the process of developing the sensitivity of children, that is, students, towards the environment and sustainable development. Considering that systematic upbringing and education for the environment and sustainable development begins in preschool institutions and schools, educators and teachers have a significant role in this. Therefore, the connectedness to nature of the educators and teachers themselves is very significant. In this paper, the role of teachers in schools and their connectedness to nature is considered in particular as a significant component of their practice of working with students in education for the environment and sustainable development. The aim of this research was to determine connectedness to nature of primary school teachers. The research was conducted through an online survey created via Google Forms during October and November 2021. The participants (N=109) were primary school teachers from Lika-Senj County and Karlovačka County. The results of the research showed that teachers estimate their connectedness to nature as high. The research showed that, according to their own assessment, teachers often behave pro- environmentally. The results showed that there is a statistically significant connection between connectedness to nature and pro-environmental behavior and previous education in the field of ecology, environment and sustainable development. Also, the results showed that there is a statistically significant difference between teachers who have been educated in the field of ecology, environment and sustainable development compared to teachers who have not been educated on these issues. The results of the research can serve as guidelines for teachers' initial education and professional improving directed toward training about this topic.