The research investigates the impact of internal lean practices (ILP), green operations practices (GOP), and enterprise resource planning (ERP) on operational performance (OP) in Saudi Arabian manufacturing companies, with a focus on the mediating role of supply chain integration (SCI). Data from 219 employees informed the study, which employed a quantitative research approach and a cross-sectional design. SPSS multiple regression analysis revealed positive and statistically significant effects of ILP, GOP, and ERP on both SCI and OP. ILP significantly influenced SCI and, indirectly through SCI, positively affected OP. Similarly, GOP demonstrated a positive impact on both SCI and OP, indicating a mediating relationship. ERP practices significantly influenced both SCI and OP, with SCI mediating the relationship between ERP dimensions and OP. These findings contribute to theoretical understanding and offer practical insights for Saudi Arabian manufacturing companies, highlighting the strategic importance of improving ERP systems, GOP, and ILP to enhance SCI and consequently OP. The research underscores the critical role of SCI in advancing sustainability and operational efficiency.