Based on the investigation of Harvard University’s doctoral dissertations on literature in the past 20 years, this paper finds that there are four main types of topics in these dissertations, namely, the general type, the descriptive type, the viewpoint type and the ideological type. These topics are interdisciplinary, and have crossed field, time and space, media and language. This paper argues that when deciding thesis topics doctoral students in prestigious American universities, represented by Harvard University, always adhere to the pioneering principle, are guided by problem awareness, and pay attention to the innovation, academic rigor and systematicity of topic selection. These findings are instructive and valuable for foreign literature doctoral students in domestic universities and scientific research institutions in determining thesis titles, and also have certain value for the cultivation of doctoral students’ academic literacy and the improvement of their research ability.