This study theoretically and empirically examined whether the traditionally accepted "gradual internationalization process" can be applied as-is to Korean firms' entry into China in relation to the internationalization process that firms choose when expanding overseas, while also empirically identifying the internal and external corporate determinants distinguishing the "gradual internationalization process" from the "rapid internationalization process." Based on empirical analysis of 186 firms that entered China, it was established that Korean firms' investment in China utilizes not only the traditional "gradual internationalization process" but also the "rapid internationalization process" to a considerable extent. The analysis of determinants for the choice between the two internationalization processes revealed that among internal corporate factors, strategic flexibility, overseas business experience, and competitiveness in the domestic market, and among external corporate factors, the host country's market potential, influenced the selection of the "rapid internationalization process." However, among internal factors, firm size and top management's commitment to internationalization, and among external factors, the host country's investment incentives, were found to have no significant influence. Meanwhile, overseas business experience and host country market potential showed unexpected negative results, presenting a distinctive pattern. This suggests that while Korean firms' investment in China is being carried out in a notably challenging and venturesome manner, firms are making strategic choices not to pursue the "rapid internationalization process"—which presupposes mass production—in consideration of weakened competitiveness in the host market.