The rapid expansion of internet connectivity, smartphone adoption, and digital payment systems has transformed consumer purchasing behavior in emerging economies. Countries across Asia, Africa, Latin America, and Eastern Europe have witnessed unprecedented growth in online retailing and digital marketplaces. This study investigates the determinants of online consumer behavior in emerging economies, focusing on technological adoption, trust, social influence, digital payment systems, income levels, and cultural factors. A quantitative survey involving 600 online consumers from selected emerging economies was conducted. The findings reveal that convenience, mobile accessibility, social media engagement, and secure payment mechanisms significantly influence online purchasing decisions. Trust and digital literacy emerged as critical mediating factors in consumer adoption of e-commerce platforms. The study provides theoretical and practical insights for businesses, policymakers, and digital marketers aiming to expand operations within emerging markets.