Objective To investigate the knowledge needs and psychological characters of the mothers of premature infants, providing the basis for continuous nursing. Methods WeChat group of mothers of premature infants was established and 43 group members were included. Chatting records of the WeChat group from September 2018 to January 2019 were extracted and classified into relevant topics. The topics with the most conversations or more than half of the participants and the topic related to the psychological experiences of mothers of premature infants were further analyzed. Results Mothers of premature infants had a large knowledge need for the care for premature infants, especially the knowledge about the growth and development management of premature infants and disease management of premature infants. Moreover, some mothers of premature infants had negative psychological feelings. Mothers with different family monthly income, educational levels, pregnancy duration, different weight and hospitalization cycles of their infants, had different chatting topics, which differences were significant (P<0.05). Conclusion In continuous nursing for mothers of premature infants, education on the care for premature infants should be strengthened and comprehensive measures of mental health should be undertaken. Additionally, the method of analyzing chatting records seems reliable and can be applied in future studies.