Vanichchinchai A.Mahidol University2023-06-182023-06-182022-01-28International Journal of Lean Six Sigma Vol.13 No.1 (2022) , 232-25220404166https://repository.li.mahidol.ac.th/handle/20.500.14594/84410Purpose: This research examines the impacts of ISO 9001 certification on lean manufacturing (LM), supply chain relationship (SCR) and their sub-constructs Design/methodology/approach: Data was collected from 516 manufacturers in Thailand. Structural equation modeling was applied to analyze the hypotheses Findings: It was found that ISO 9001 certification significantly affects overall LM, its facility and quality sub-constructs, overall SCR, its supplier coordination, customer collaboration and customer coordination sub-constructs. ISO 9001 has insignificant impacts on production, purchasing and distribution of LM, and supplier collaboration of SCR. Originality/value: This study is one of the first research to present insights into the impacts of ISO 9001 as a certificate rather than as a set of management practices on LM, SCR and their sub-constructsDecision SciencesArticleSCOPUS10.1108/IJLSS-10-2020-01642-s2.0-8511045508920404174