Drawing from the phenomenographic perspective, an exploratory study investigated Chinese teacher educators' conceptions of teaching Nature of Science (NOS) to pre-service science teachers through semi-structured interviews. Five key dimensions emerged from the data. This paper focuses on the dimension, NOS content to be taught to pre-service science teachers. A total of 20 NOS elements were considered by the Chinese science teacher educators to be important ideas to be taught. It was also found that among these educators, whether focusing on the classical or contemporary NOS elements in NOS instruction was a prominent controversy. After explaining the criteria for differentiating between classical and contemporary NOS elements, this paper reports the specific NOS elements suggested by Chinese science teacher educators in this study. Afterward, it describes how all educators in this study were categorized in term of NOS content taught by them to pre-service science teachers. In the end, it discusses three factors influencing the decision on NOS content to be taught, i.e., view of the concept of NOS itself, vision of teaching NOS, and belief in general philosophy.