This study investigated the effects of service guarantees perceived by commercial travel agencies on repurchase intentions and the moderating effect of brand image in these relationships. As a result of the empirical analysis, the following results were derived. First, as a result of verifying the relationship between service guarantee and repurchase intention, service guarantee had a negative (-) effect on repurchase intention. This can be seen that a high perception of the service guarantee decreases the repurchase intention. Second, as a result of verifying the moderating effect of the brand image in the effect of service guarantee on the repurchase intention, it was found that only brand trust among the brand images showed moderating effect. This can be seen as a high perception of brand trust among the brand image, the service guarantee increases the repurchase intention. In particular, when the global OTA is expanding its scope in the commercial travel market through a strong brand, offline commercial travel agencies should secure competitiveness through face-to-face services and company-specific services that only offline have, and the limitations of global OTAs. Due to restrictions on the application of domestic laws, it is necessary to secure competitiveness through a specific service guarantee system in response to infringement of consumer rights such as refund, system, and payment problems.