Humanity faces an escalating environmental crisis, with waste management emerging as one of the most pressing challenges of the modern era. The accumulation of waste has significant environmental, social, and economic consequences, threatening ecosystem health and human quality of life. Education plays a critical role in addressing this challenge by fostering sustainable development and cultivating environmentally responsible citizens. Environmental Education (EE) and Education for Sustainable Development (ESD) are essential for developing environmental literacy from an early age. Early childhood and primary education represent key periods for shaping positive environmental attitudes and behaviors, as children are highly receptive to knowledge and values at these stages. Consequently, the preparedness of educators, particularly pre-service teachers, is crucial in influencing future generations’ environmental perceptions. This study investigates the knowledge, attitudes, and self-efficacy of future Greek pre-service teachers in waste management, highlighting their potential role as agents of environmental change.