Background. WeChat is the most widely and frequently used mobile social media in China and has profoundly integrated into the daily life of many Chinese people. A variety of medicine-related information may be found on WeChat. As users of WeChat, doctors often access health-related information and even provide a variety of medical services or participate in various types of mobile communication with patients. Objective. This study is the first attempt to quantitatively explore the approaches by doctors of acquiring medical knowledge using Internet resources especially social media such as WeChat to access knowledge. Methods. A self-administered questionnaire was designed, distributed, collected, and analyzed utilizing the online survey tool Sojump. WeChat was adopted to randomly release the questionnaires using snowball sampling and collect the results after a certain amount of time. Results. 292 valid questionnaires out of 314 questionnaires by clinical doctors were analyzed. Regarding the current status of accessing medical knowledge among doctors, more than 60% of the doctors regularly used the Internet to search for medical knowledge, 19.86% used WeChat as a channel to acquire medical knowledge, and only 23.97% were satisfied with acquiring medical knowledge through the Internet. Regarding the frequency of WeChat usage, nearly 40% of the doctors accessed WeChat more than 20 times per day and over 70% used WeChat for over half an hour every day. Regarding the status of accessing medical knowledge through WeChat, nearly half (47.26%) of the doctors stated that they often read professional medical articles on WeChat and the most common channel is friends’ moment sharing and public account subscriptions, with selection rates of 59.93% and 60.27%, respectively. The most desirable mode of acquiring medical knowledge through WeChat was the following: “professional medical knowledge from peers, with a reminder.” Conclusion. WeChat has become a nonnegligible means of acquiring medical knowledge for busy Chinese physicians in a mobile environment. Further evaluation and improvement of the quality of medical knowledge on WeChat are needed. The recommendation of individualized articles through social media may become another contributing factor for doctors to acquire medical knowledge effectively and efficiently.