With the rise of micro media, the library’s traditional knowledge services and its publicity and promotion methods have been challenged. This study investigates the marketing and promotion of knowledge services through micro media in university libraries. Based on the dynamic model of knowledge service marketing promotion in university libraries, this paper conducts network research and analysis on the library knowledge service microblog, WeChat, and microfilm marketing of 42 world-class universities in China. The results show that among 42 university libraries, microblog and WeChat have a high opening rate but do not attach importance to late marketing management and maintenance (microblogs’ opening rate is 83.3%, the proportion of people paying attention is 20%). The number of knowledge service outlay exceeds 1,000 accounts (28.6%). The rate of consultation feedback within one day is 17.14%. The official WeChat account number has 97.6% of libraries. The ratio of WeChat push at least once a week is 68.3%, and the rate of consultation feedback within one day is 17.07%. Microfilm marketing is not valued as a whole (the release rate of microfilms is only 9.5%). Successful microfilm marketing (such as Tsinghua University’s “falling in love with the library” series with 7,320 views/day) helps to improve the communication efficiency of knowledge services and brand awareness. This study confirms that micro media marketing has not been fully developed and utilized. University libraries should take user experience, media technology, resource reserve, service content, account publicity, and operation as the starting point to improve user viscosity.