The integration of sustainability in higher education has been globally recognized as essential for preparing future educators who can foster ecological awareness, responsible citizenship, and sustainable practices. However, research in the Philippine context, particularly among preservice teachers, remains limited. This study addressed this gap by examining preservice teachers’ knowledge, attitudes, willingness to act, behavior, and self-efficacy toward sustainability, with attention to gender as a demographic factor. Using a quantitative, cross-sectional survey design, data were collected from 240 preservice teachers enrolled in state universities. The instrument covered six constructs—knowledge, attitudes, willingness to act, behavior, self-efficacy, and affective dimensions. Descriptive statistics revealed moderately high knowledge (M = 3.84, SD = 0.86), positive attitudes (M = 4.08, SD = 0.79), strong willingness to act (M = 4.18, SD = 0.85), positive sustainable behaviors (M = 3.90, SD = 0.81), and adequate self-efficacy (M = 3.77, SD = 0.81). Independent samples t-tests, supported by effect size analysis, showed no statistically significant differences between male and female preservice teachers across all constructs. These results suggest that gender may not substantially influence sustainability dispositions among future teachers, pointing instead to the shared impact of teacher education programs in shaping sustainability mindsets. The findings underscore the importance of systematically integrating sustainability into teacher education curricula to develop consistent competencies across demographic groups. Strengthening teacher preparation in this area can help higher education institutions advance the realization of SDG 4.7 and the transformative vision of Education 5.0 in the Philippine setting.