The purpose of this study is to investigate the causality between national culture and international tourism demand. In order to achieve the purpose of this study, an empirical analysis was conducted on the causality between Korean and Japanese culture and Vietnamese tourism demand based on the Hofstede National Cultural Dimensions. Prior to the empirical analysis, Korean and Japanese culture were compared and analyzed based on the Hofstede's six cultural dimensions, and Cultural distance representing cultural differences between countries was measured. Korean culture and Japanese culture showed the greatest difference in cultural dimensions of masculinity and individualism. As a result of measuring the cultural distance between Korea and Japan, which are tourism destination countries, and Vietnam, the country of origin for tourists, it was found that Korean culture is closer to Vietnamese culture than Japanese culture. In this study, based on the gravity model, the effect on tourism demand in Vietnam visiting Korea and Japan was analyzed by setting GDP and exchange rate as an economic factor and cultural distance as a cultural factor. As a result of the analysis, it was found that all the variables used in this study model had a valid effect on the demand for Vietnamese tourism visiting Korea and Japan. n this study, cultural distance variables, which were a major concern, were found to have a negative (-) effect on the demand for Vietnamese tourism visiting Korea and Japan. In other words, it can be estimated that the farther the cultural distance is, the more negatively it affects tourism demand. In particular, cultural distance variables, which are cultural factors, were estimated to have a greater influence on tourism demand in Vietnam than economic factors such as GDP and exchange rates. These results can be interpreted that for Vietnamese tourists visiting Korea and Japan, culture is an important factor in choosing tourist destinations, and culturally similar destinations are selected.