As one of the garment producers in the world, Indonesia continues to strive to increase its competitive advantage in the current growth and development. Various factors can influence the improvement of competitive advantage in the garment sector. This study investigates the competitive advantage in the garment sector as influenced by supply chain strategy and supplier environment, moderated by environmental uncertainty in garment companies in West Java. The population of this study was 250 garment companies, and the sample was 152 respondents. Data were collected through questionnaires and analyzed using Partial Least Square (PLS). The findings of this study are (1) supply chain strategy is positively influenced by supplier environment; (2) competitive advantage is influenced by supplier environment and supply chain strategy; and (3) environmental uncertainty can moderate supplier environment and supply chain strategy in influencing competitive advantage.