This study explores the determinants of strategic agility among publicly listed suppliers within Xiaomi Auto’s electric vehicle (EV) supply chain, with a specific focus on the joint effects of Human Resource Development (HRD) interventions and financial performance. In the context of the EV sector’s rapid technological change and market uncertainty, strategic agility has become a critical capability for sustaining competitiveness. Drawing on Dynamic Capabilities Theory and Human Capital Theory, the study employs a quantitative, deductive approach using secondary panel data spanning 2019 to 2023. The sample comprises five core suppliers in Xiaomi’s EV ecosystem: CATL, Desay SV, Goertek, Sunny Optical, and Luxshare Precision. Strategic agility is measured through Return on Assets (ROA), with explanatory variables including R&D Intensity, Inventory Turnover, Training Cost per Employee, Revenue per Employee, and Total Assets (as a control). The analysis applies descriptive statistics, Pearson correlation, multiple linear regression, and collinearity diagnostics through variance inflation factor and condition index measures. Results indicate that Inventory Turnover and R&D Intensity significantly improve ROA, whereas HRD variables, despite strong correlations, are affected by multicollinearity. The findings offer practical implications for how operational efficiency and workforce investment jointly influence agility within high-technology supply networks.