<p>This study examines consumers’ intentions and behaviors toward sustainable consumption and analyzes the moderating influence of consumers’ environmental knowledge. Additionally, it investigates the impacts of social media influencers’ influence and sponsored ads on consumers’ sustainable consumption intention and behavior. The study draws inspiration from the Stimulus-Organism-Response (SOR) model. The purposive sampling technique, which is nonprobability-based, was utilized to gather 404 valid samples from respondents who had either previously purchased or intended to purchase sustainable items. Data analysis was conducted using IBM Statistics 25 and SmartPLS 4.1.1.2. The direct and indirect effects of social media influencers, sponsored ads, sustainable consumption intention, and sustainable consumption behavior corroborated the presented hypotheses. Furthermore, the moderating influence of environmental knowledge did not demonstrate relevance in sustainable consumption behavior. The study findings offer significant insights for social media influencers to craft targeted message appeals within specific industries, such as fashion, footwear, cosmetics, and FMCG, to enhance sustainable consumer participation and facilitate behavioral change. This study enhances the literature on SOR model by examining the influence of social media influencers and sponsored ads on sustainable consumption intentions and behaviors while considering the moderating effect of environmental knowledge strength within the context of Bangladesh, a developing country. It underscores the need to advocate for and support sustainable consumption intentions and behaviors on social media platforms, offering significant information for general consideration.</p>