The objective of this research is to explore if TQM firms execute various organizational management practices significantly different from non-TQM firms in the ASEAN automotive supply chain. Datasets were collected from ASEAN automotive Original Equipment Manufacturers (OEMs) and their Tier 1 and 2 suppliers. Then, datasets were tested by using statistical analysis. The results show that seven TQM practices including leadership, strategy and planning, customer focus, information and analysis, people management, process management, and supplier involvement are significantly higher in TQM firms than Non-TQM firms. ASEAN OEM suppliers in the automotive industry can use the results of this study to select and deploy suitable TQM practices to enhance their competitiveness in the first instance in the automotive sector and then to other value-adding sectors. This study also indicates that automotive industry and others need to consider TQM practices, as an organizational innovation or organizational development intervention, along the entire supply chain.