Due to undergraduate students heavy reliance on internet-enabled mobile devices and social media applications use for information seeking, retrieving and sharing, the study was conducted to investigate users’ health information seeking behaviour on social media with specual reference to Ladoke Akintola University of Technology Teaching Hospital Library, Ogbomoso. The web of Science Core Collection and healthcare database were searched for existing literature on users’ health information seeking behaviour. The study examined the types of social media mostly used, factors facilitating the use of social media, types of health information sought on social media, and the benefits of health information to the users. Survey research design was adopted for the study in which copies of self-developed structured questionnaire was distributed to a sample size of 150 library users, while 134 were retrieved and use for data analysis. Data collected on users’ health information seeking behaviour on social media were analyzed using descriptive statistics. The findings from the study revealed that Facebook, WhatsApp, Telegram and You Tube were predominantly used for seeking health information by the respondents while the least social media used by the respondents were Flickr, MySpace and Ning. Different factors were responsible for the use of social media for seeking health information but the leading factor was sufficient knowledge and skills on the use of social media. Respondents sought information on different topics of interest as the leading topics sought for were information on health status and treatment of diseases. The benefits derived by the respondents for seeking health information on social media were enormous. Based on the findings of this study, it was recommended that the Ministry of Health, the Nigeria Medical Association and health practitioners should, as a matter of duty, make health-related information available on various social media platforms for utilization of the users, especially clinical medical students. It is also necessary to promote e-health on social media platforms in order to get quick, timely, affordable and accessible means to health information and healthcare services for improved access to mobile health.