This study proposes a model of trust formation and the role of trust among auction participants in consumer-to-consumer (C2C) Internet auctions, and empirically tests the research model with domestic Internet auction users. The research model consists of independent variables (buyer's trust propensity, institutional characteristics, perceived reputation, perceived size, and perceived benefits), mediating variables (trust in the Internet auction site, trust in the seller), and a dependent variable (auction participation intention). According to the research findings, it was demonstrated that trust in the auction site is critical for consumer auction participation in C2C Internet auctions, where the degree of transaction risk is relatively high. The trust relationships in Internet auctions were found to exhibit auction-specific trust characteristics that differ from trust in general Internet purchasing. In particular, a "trust transfer effect" was confirmed, whereby trust formed in the Internet auction site significantly influences trust in the sellers participating in the auction. It was also revealed that perceived benefits provided by Internet auctions alone do not lead consumers to participate in auctions; consumers participate in auctions only when trust in the Internet auction site has been established. Therefore, the results of this study suggest that enhancing the trustworthiness of auction sites is a prerequisite for the revitalization of Internet auctions.