Strategic supply chain management is one of the key business functions in almost every manufacturing organization. The research expecting to explore the relationship between social capital and the perceived effectiveness of strategic supply chain decisions in Sri Lankan apparel sector organizations. With respect to the positivism paradox research has been organized in line with the deductive approach. Further survey strategy through a pre-tested questionnaire has been imbedded with the sample of 122 participants from the apparel sector supply chain professionals, which is regulated by Krejcie & Morgan. This study can be recognized as a validation of the past studies within the Sri Lankan context. The statistical analysis depicts an existence of a direct positive linkage between perceived effectiveness and individual decision maker's social capital which approves the existing literature in the Western context. The study has contributed to the knowledge domain of strategic management, supply chain management, and organizational behavior by identifying the factors and how they influence strategic decision making.