In the last several years, South Korea's shipbuilders have been dominating global shipbuilding. Thus, many global suppliers in the shipbuilding industry, especially German supply companies, are eager to get the Korean major shipbuilders as their customer. This study analyzed the different ways of business behaviours of German and Korean businessmen regarding customer-supplier relations. Furthermore, this paper aims to examine the kinds of challenges the international businessmen are confronted with and how this affects everyday business between German suppliers and Korean customers, using several case examples. Finally, backgrounds of cross-cultural problems and conflicts of German-Korean business relations are identified and explained.