Food waste is a growing environmental, economic, and social challenge worldwide. This study aimed to assess the association between various socio-demographic characteristics and household food waste behaviors among university students in Italy. A cross-sectional study was conducted using a validated, online, anonymous, and voluntary-based questionnaire distributed among university students in Milan, Italy. Linear regression analyses were performed to explore the association between socio-demographic factors and anti-household food waste behaviors (preventive practice, abilities scores, and parental guidance). A total of 2779 students participated in the survey. Students residing outside Lombardy exhibited higher preventive practice scores (β = 0.11, p = 0.030). Regular smoking was negatively associated with preventive practice (β = −0.22, p < 0.001) and abilities scores (β = −0.11, p = 0.009). Cohabitation with a partner positively impacted abilities scores (β = 0.23, p = 0.007). Larger family sizes and students in scientific fields showed higher scores for parents’ guidance (β = 0.18, p < 0.001). Frequent use of food delivery apps correlated with lower scores across all categories, while anti-food waste apps had a positive effect. Socio-demographic factors significantly influence food waste behaviors among university students. Tailored public health policies and educational programs addressing these factors could effectively reduce food waste.