Ensuring sustainability through green supply chain management practices has become challenging for the textiles and garments industry. Organizations need to examine the factors of the firm’s sustainability performance and how to manage them strategically. Hence, the strategic organizational orientation can be the best approach for implementing green supply chain management (GSCM) practices to improve firm sustainability performance. This study aims to assess the impact of strategic orientation in three dimensions, such as green entrepreneurial orientation (GEO), market orientation (MO), and knowledge management orientation (KMO) on the implementation of green supply chain management (GSCM) practices and the subsequently sustainable firm performance. Data were gathered from an extensive scale survey of 266 respondents of textile manufacturing firms in Bangladesh. Data were analyzed in the structural equation model (SEM) with partial least squares techniques to justify the proposed hypotheses. The results reveal that GEO and MO have a significant positive effect on GSCM practices, affecting sustainable firm performance. Surprisingly, KMO does not have a positive impact on GSCM practices. Further, this study reveals that GSCM practices partially mediate the relationship between GEO and sustainable firm performance while MO and KMO partially mediate the relationship between GEO and GSCM practices. Overall, findings help textiles firm management comprehensively understand the implementation strategies of GSCM practices in operations and reconfigure accordingly in the competitive business environment while improving firm performances. This study is the first to investigate the effect of strategic orientation on GSCM practices implementation in the textiles industry from the context of an upstream operation with a comprehensive understanding of the factors while reducing environmental impact.