The fast rate of digitalisation of business processes has made e-commerce adoption to be an indispensable element in the competitiveness of Micro, Small and Medium Enterprises (MSME) sector. While prior studies have extensively examined Technology-Organisation-Environment (TOE) framework, limited research has integrated innovation attributes, firm-specific capabilities, and institutional forces to explain performance outcomes. Addressing this gap, the present study examines the impact of e-commerce adoption on MSME business performance by integrating the TOE framework with Diffusion of Innovation (DOI), Resource-Based View (RBV), and Institutional Theory. The primary data was collected from 387 MSMEs operating in Delhi through a structured questionnaire. The use of exploratory factor analysis confirmed a thirteen-factor measure structure, and convergent and discriminant validity were determined using confirmatory factor analysis (CFA). The analysis based on principal component regression showed that technological and environmental factors (especially IT knowledge, governmental support, competition pressure, and market readiness) positively contributed to business performance due to the adoption of e-commerce. The effects of organisational constructs like culture, structure, and managerial support were relatively weak. The integrated theoretical approach demonstrates strong explanatory power as the model explained 72.9% of the business performance variation (R² = 0.729). The implications of these findings include the extension of the TOE framework to the context of an emerging-market environment and provide substantive implications to MSME managers and policymakers who strive to strengthen the initiatives aimed at digital transformation..