Abstract: This paper examines the influence of Tong Cheng writing theories on Yan Fu’s choice of word, textual structure, and language style in the translation ofThomas Huxley’s Evolution and Ethics, in view of the close relationship between Yan Fu and Tong Cheng School. Based on careful perusal of Yan’s translation, it is found that Yan Fu intends to save the ontological value of writing by elegant diction and sentences with musical tone. When inventing new terms, Yan Fu resorts to Chinese exegesis, researching on etymology, shape and meaning of English original, Chinese characters and existent Japanese translations to ensure his coined terms truly correspond with the original. What’s more, Yan Fu reconstructs composition, adds notes and commentary to support his own argumentation and fulfill social function of translation. Finally, it is concluded that Yan Fu actually sets a higher standard on translator, translation course, and translation works by applying the writing theories of Tong Cheng School into translation.