How the interface of state law and indigenous market laws contributes to peacebuilding in Nigeria is an unexplored question that demands attention. First, law, human security and peace are interrelated through the cultural ideas and norms that inform human behaviour. Second, the co-existence of normative orders in Africa favours a top-down approach that inadequately acknowledges indigenous law, neglects its economic, cultural and religious influences, and thereby affects human security. Based on key informant interviews, focus group discussions and observation of markets in southern Nigeria, this article finds that although indigenous market laws are much altered, their foundational values inform market union constitutions, bye-laws and dispute resolution mechanisms. Union officials draft these laws with the assistance of Western-trained legal practitioners and apply them in close co-operation with state organs, who recognize market tribunals as quasi-judicial bodies. The article urges policy attention on the manner people adapt indigenous market laws to socio-economic changes.