This article analyses the role of Christian missionaries in the Modernization of China. The paper will examine the historical developments of Christianity's arrival in China, and the function of Jesuit and Protestant missionary groups. Furthermore, it will indicate that although the primary purpose of all missionaries was to evangelize the Chinese heathen, this developed gradually as historical and cultural conditions in China and the West changed. How did the conditions for this development come about? In sum, there were three categories of factors influencing this development including the demands of the "Treaty system", and the new relations of the weakened Qing government with the Western powers; the Protestant theological-social disputes in the West over the impossibility of Evangelization of other people in the world; China's particular climate and catastrophic natural events such as drought, floods and the like. In contrast to Jesuits, Protestant missionaries replaced the policy of Vernacularation with that of Inculturalization; replaced the Bottom-up Conversion with Top-down Conversion and, more important, they replaced Modernization with Evangelization. In sum, the religious motives of the Christian missionaries, unwittingly, made Chinese society and the government more rational, and more secular. They contributed to the emergence of new regimes and movements and elites that eventually acted against the missionaries themselves. In this paper, the Weberian approach is used for analysis of actions and subjective meanings of Christian missionaries.