Drawing on causal chain analysis, this study investigated the interconnected pathways through which sustainability-oriented organisational culture (SOOC), sustainability-oriented employee literacy (SOEL) and sustainability-oriented employee performance (SOEP) influence sustainable supply chain performance (SSCP) within the automotive industry of Sichuan Province, China. A quantitative research design was adopted, involving survey responses collected from 1,050 employees and managers and analysed using partial least squares structural equation modelling (PLS-SEM). Empirical evidence supported 6 of the 9 proposed hypotheses. Among the estimated relationships, SOOC exhibited the strongest direct effect (β = 0.805), whereas the relationship from SOEP to SSCP demonstrated the highest coefficient (β = 0.815). The findings further established the significant serial mediating roles of SOEP and SOEL, with a reported coefficient of β = 0.389 for their relationships with SSCP. However, the direct association between SOOC and SSCP was statistically insignificant. These results contribute to theoretical understanding by identifying human capital as a critical mechanism through which organisational cultural orientations translate into sustainability-related supply chain outcomes. From a managerial standpoint, the evidence highlights the importance of strengthening employees’ sustainability literacy and performance capabilities alongside cultivating an organisational culture centred on sustainability to achieve measurable improvements in supply chain performance.