This study examines the structural transformation of Vietnam’s export competitiveness across 97 Harmonized System (HS) 2-digit industries over 2005–2024. To overcome the limitations of single-indicator measures, it constructs a multidimensional Composite Competitiveness Index (CCI) by integrating Revealed Comparative Advantage (RCA), Market Share (MS), Trade Competitiveness (TC), and Relative Trade Advantage (RTA) using the Entropy Weight Method and Coefficient of Variation approach. The results show that Vietnam’s export structure has shifted from raw-material dependence and basic assembly toward deeper processing, supply-chain localisation, and technology-intensive manufacturing. Competitiveness has weakened in several primary sectors, but risen strongly in processed agriculture, upstream textile inputs, and heavy and high-technology industries. The study contributes by offering a comprehensive sector-wide assessment of Vietnam’s export competitiveness, a more robust objective weighting framework for composite trade measurement, and new empirical evidence on value-chain upgrading in an emerging economy. The CCI also provides a practical monitoring tool for identifying competitive strengths, structural weaknesses, and policy priorities for industrial upgrading and domestic value creation.