Given the crucial role of curriculum in the success of educational systems, the integration of new cognitive approaches in curriculum design should be considered. Accordingly, the present study aimed to identify the dimensions and components of a systems thinking curriculum with a heutagogical approach in lower secondary education. This study is applied in terms of purpose and qualitative in terms of implementation. The research population included eight experts and university faculty members specializing in curriculum planning and educational psychology, who were selected through purposive and snowball sampling methods based on the principle of theoretical saturation. Thematic analysis using a theme network approach was employed to analyze the data. The findings of the study indicated that for designing a systems thinking curriculum model with a heutagogical approach in lower secondary education, within the overarching theme of curriculum, 26 basic themes were categorized under seven organizing themes: structural reform, process management, modern education, promotion of research, utilization of technology, foresight, and understanding complexity. In the overarching theme of implementation requirements, 15 basic themes were classified under five organizing themes: structural, legal, functional, systemic comprehensiveness in macro design, and understanding dimensions and relationships in educational processes. Furthermore, in the overarching theme of implementation effects, 23 basic themes were identified under eight organizing themes: enhancement of students' academic capabilities, development of students' social competencies, improvement of students' psychological competencies, advancement of students' various thinking skills, understanding systemic relationships and modeling, adaptability and comprehension of complex environments, flexibility, and enhancement of teachers' teaching competencies.