Amid the growing popularity of Japanese cuisine, soy source—an indispensable Japanese seasoning for this cuisine has also been attracting attention. However, demand for soy source has been declining due to dietary diversification and Japna’s shrinking population, raising concerns about the decreasing number of small breweries. This is especially concerning given the important role local breweries play in creating and preserving regional culinary heritage. Therefore, this study investigates the online direct selling activities of local soy sauce breweries and the factors contributing to their success. To this end, we employed ordered logit models using data collected from breweries’ websites. The estimation results revealed that breweries producing value-added soy source, using traditional wooden tubs, and receiving awards exhibited stronger online sales performance. In contrast, overseas expansion efforts were limited, primarily due to constraints in managerial resources.