The current design of supply chain (SC) for small garment manufacturing companies in the Philippines has not incorporated green practices to address environmental issues. In the adverse environmental effect of industries worldwide, green supply chain management (GSCM) has appealed to companies to reduce the occurrence of such issues. This study evaluated the current SC design and operations of small garment manufacturing companies with respect to their environmental practices. Using the green supply chain operations reference (G-SCOR) model, data from the subject companies were evaluated based on fifteen (15) indicators of the six (6) attributes which include reliability, responsiveness, agility, cost, asset management efficiency, and green practices. Results revealed that the small garment companies have excellent performance in terms of perfect order fulfillment (POF) and working capital turnover (WCT) while good performances were observed in total SC management cost (TSCM), cost of goods sold (COGS), awareness management, and waste management. In contrast, poor performances were evident in upside supply chain adaptability (USCA), downside supply chain adaptability (DSCA), fixed asset turnover (FAT) ratio, implementation of green procurement, recycled materials, and carbon dioxide (CO₂) gas emission. A multiple regression analysis model was also created to determine the significant factors contributing to GSCM. Results revealed that among the indicators, CO₂ emission, waste management, and COGS significantly influence the GSCM. To improve the companies’ G-SCOR performance, it is recommended that appropriate environmental practices such as green procurement, recycling, waste management, and reverse logistics should be implemented. Proper information dissemination campaigns should also be done in the companies so that the employees may be educated and be involved in the GSCM practices.