Extra-role behavior, which has been primarily studied in the field of organizational behavior, has recently attracted attention in the marketing field in the form of customer-oriented extra-role behavior. However, most studies on extra-role behavior have focused on employees in the service industry, and research remains insufficient regarding organizations where such behavior is highly likely to occur, particularly in distribution channels formed through organic relationships among members. To address this issue, this study empirically examines the antecedent variables of extra-role behavior among distribution channel members from four existing perspectives that explain inter-organizational relationships: the trust-commitment perspective, the dependence perspective, the transaction cost theory perspective, and the relational norms perspective. For empirical analysis, this study collected a total of 320 questionnaires from store owners or managers across corporate channel structures, contractual channel structures, and traditional channel structures in the domestic distribution industry, and analyzed the data using structural equation modeling. The results of the data analysis revealed that in buyer-seller relationships within distribution channels, the buyer's trust and commitment strengthened extra-role behaviors such as external representation, internal influence, and service delivery. Dependence, transaction-specific investment, and relational norms partially strengthened these behaviors, while opportunism weakened them.