Abstract: This study sought to determine the average time spent on social media by medical undergraduates in University of Uyo, Akwa Ibom State, Nigeria and to determine the relationship between social media use and disturbances of sleep quality and quantity amongst medical undergraduates in University of Uyo. It was a cross sectional population based study among 208 medical students in University of Uyo, Southern Nigeria. They were randomly selected with a proportionate stratified random sampling method and data collection was done using a self-reporting anonymous questionnaire. Social media use was assessed using multiple items reflecting the frequency, volume, location and platform of social media use. The average time spent on social media by respondents was 1-3 hours. Proportionately, the most time was spent on Facebook. In models that adjusted for all covariates, participants who spent more time on social media per day had significantly greater odds of having disturbance of sleep quality. Compared with those who spent more than 3 hours per day on social media, those who spent 1-3 hours per day had an adjusted odds ratio of 4.59 (95%CI: 4.14-5.48, p value < 0.001) for sleep disturbance. A significant association was reported between volume of social media use and sleep disturbance. This has important clinical implications for the health of young adults. Future work would focus on the interactions on the various social media platforms that make their use significant to young adults.