明末耶穌會士為傳教而輸入西學，將亞里斯多德四元素說以四行說引入，而有了 陰陽五行說與四元素說兩種不同理論的遭逢。由於陰陽五行說與四元素說分別代表朱熹理學 與耶穌會士兩種世界觀中解說自然現象變化的理論，本文旨在從耶穌會士傳教的立場，以兩 種世界觀的遭逢為背景，來探討明末西方四元素說的傳入。在耶穌會士的世界觀中，四元素 、萬物與人的靈魂都是出自造物者之功。為了傳教，四元素說係從兩個方向關連到五行說： 一方面， 基於自然知識可以用來證明造物主的存在，批駁異論，<< 天主實義 >> 中反映了 理學與耶穌會士兩種世界觀的爭議，為討論天主與人魂問題而牽涉四元素說與五行說。另一 方面，解說自然現象變化的四元素說，對引導中國士人轉信基督教理有所幫助。依此 << 乾 坤體義 >> 引入四元素說來批判五行說，排除金木在外，並將分布於三域的氣納為一行，來 解釋地域內大氣現象之變化，使四元素說理論中國化而成為四行說。 利瑪竇之後， 熊三拔 << 泰西水法 >>、高一志 << 空際格致 >> 與傅汎際 << 寰有詮 >> 等作品，在進一步依據 亞里斯多德 << 氣象學 >> 或 << 論天 >> 的傳統來推廣四行說時，仍不忘提及造物主與四 行和萬物的關係。

　　　　　While five-phases theory (metal, wood, water, fire and earth) was still a dominant theory for Chinese understanding of natural phenomena in late Ming, Jesuits transmitted western learning, including Aristotelian fourelements theory (fire, air, water and earth), for the propagation of Christian faith. In fact, the encounter of these two theory of matter reflected the confrontation between Jesuit and Neo-Confucian (sep. Zhu Xi's) worldviews. In this paper the author will take the position of Jesuits to see how did they transmit western four-elements theory in this background. At the time Jesuits and Neo-Confucians had different views on the origin of the universe, theory of matter, and the nature of human soul. In the Tienzhu shiyi 天主實義， in which Jesuit and Zhu Xi's worldviews are encountered, Matteo Ricci mentions four-elements theory and five-phases theory in the context of his proofs of the existence of the Creator and the immortality of human soul. In the Qian kun ti yi 乾坤體義， in order to establish four-elements theory, Ricci attacks Chinese five-phases theory on the one hand, however, he barrows some Chinese terms to make four-elements theory more accommodated to Chinese literati on the other hand. Later, in the Aristotelian traditions of Meteorology and On the Heavens, de Ursis, Vagnoni and Furtado respectively extends four-elements theory in Taixi shuifa 泰西水法， Kongji gezhi 空際格致 and Huan you quan 寰有詮 without forgetting to propagate Christian faith.