Academic writing is the process of authors’ interaction and communication with readers. Based on Yang's classification of evidentiality and self-built corpus, this study examines and compares the characteristics of Chinese and western authors’ use of evidentiality in second language academic writing. The major results include: 1) Evidentials are universal in research papers. Chinese authors’ less use of evidentials indicates their tendency to conceal personal opinions to offer more objective arguments; 2) Both Chinese and western authors prefer reporting and inferring evidentials, owing to the style of natural science and the language practice of the subject; 3) The frequency of English authors’ sensory and belief evidentials is significantly higher than that of Chinese authors due to the different cultural backgrounds; and 4) As to the specific realization of each evidential type, the commonality and difference coexist.