This study examined the physical activity and dietary patterns of university students in Nairobi County and compared to their weight status. The study was a cross-sectional analytical design with a sample of 260 undergraduate students randomly selected from two private and two public universities. A semi-structured questionnaire was used to gather information from students. Students weight and height measurements were also obtained. Data was analyzed using SPSS version 22. The study results showed that 53.5% of the students met the recommended levels of moderate physical activity and 18.8% of the students met the recommended levels of vigorous physical activity. Majority of the students consumed fast foods sweetened beverages and pastries most times in a week. The study also showed that 31.2% of the students were overweight and 6.2% were obese. The study reveals that most students did not achieve the recommended levels of vigorous physical activity and showed some poor dietary patterns. Findings show clear evidence of high prevalence of overweight among university students but focus should be on fitness rather than fatness. Efforts should be made to promote physical activity participation and good dietary practices within university environments.