<p>Soybean seeds are highly susceptible to rapid deterioration during storage, posing a critical constraint on their agricultural productivity and seed security in tropical environments. The present study aimed to evaluate physiological and biochemical traits associated with seed longevity using correlation and principal component analyses. Thirty-seven diverse soybean genotypes were monitored over a twelve-month period under natural uncontrolled storage condition to assess changes in seed physiological parameters and metabolic constituents. Correlation analysis revealed that the progressive loss of germination and vigour was fundamentally associated with the depletion of total soluble sugar reserves and the simultaneous accumulation of lipid peroxidation products. Terminal longevity status evaluation via PCA-1 effectively discriminated genotypes along a clear gradient of metabolic competence and structural integrity. While, PCA-2 successfully captured coordinated ageing dynamics, demonstrating a strong contrast between functional performance decline and membrane destabilisation. The findings underscored the pivotal role of carbohydrate metabolism, membrane integrity, and oxidative protection as the primary biological factors associated with seed longevity. This integrative multivariate analysis successfully identified ageing-tolerant and sensitive genotypes that may serve as valuable parent material in breeding programmes aimed at improving soybean seed longevity and storage resilience.</p>