This doctoral thesis primarily aims to understand the role that environmental education occupies in the personal, formative, and professional life trajectories of basic education teachers in São Gonçalo who implement environmental education practices in schools. The study seeks to recognize to what extent these trajectories contribute (or not) to the construction of an environmental teaching identity. It also aims to explore the relationships between teachers life trajectories, their teaching practices in environmental education, and the socio-environmental issues in São Gonçalo. The research is justified by the importance of contextualized environmental education in schools to form citizens committed to environmental preservation. Additionally, it seeks to identify elements that facilitate the construction of teaching identity and professional development concerning environmental education. This is a qualitative research study employing questionnaires and interviews, analyzed according to Bardin s content analysis method. The study involved 27 basic education teachers who reported conducting environmental education activities in schools in São Gonçalo. Out of these, eight teachers were interviewed to deepen the understanding of their life trajectories and environmental education practices. The theoretical framework includes studies on environmental education (Sauvé, Layrargues, Loureiro, and Guimarães), definitions of ecological subject (Carvalho), identity and professional socialization (Dubar), teacher knowledge (Tardif and Shulman), and the teaching profession and life histories of teachers (Goodson, Nóvoa, and Gatti). The influence of environmental/socio-environmental issues on teachers life trajectories results in a diversity of environmental teaching identities shaped by experienced socializations and social interactions unique to everyone, influencing their conceptions of environmental education and teaching practices. Throughout the investigation, we understand family, school, formative institutions, and professional practice as relevant influences on teachers professional practice in environmental education. Finally, we conclude that diverse environmental teaching identities exist, shaped by each teacher s life trajectory and their relationship with educational institutions in all their complexity and multiplicity.