This article develops a set of indicators to assess social capital of the Vietnamese pepper supply chain in the three main aspects, i.e. trust, norm, and network. Likert scale is used to quantify the magnitude of the social capital and to calculate the social capital index. Then, the research evaluates the impact of social capital on the performance of the Vietnamese pepper supply chain using the Structural Equation Modelling (SEM). Finally, implications of the influence of social capital in supply chain management are discussed. This study contributes to the literature of social capital and SEM methodology.