Background Circadian eating patterns, referring to the timing and regularity of meal intake relative to the body's internal clock, are increasingly recognized as important determinants of metabolic health among university students. However, empirical evidence on how the university food environment influences circadian eating patterns remains scarce, particularly within Nigerian tertiary institutions. This study assessed the influence of the university food environment on the circadian eating patterns of undergraduate students at the University of Medical Sciences, Ondo (UNIMED). Methods A descriptive cross-sectional study was conducted among 302 undergraduate students selected through a multistage sampling technique. Data were collected using a structured, facilitator-administered questionnaire assessing socio-demographic characteristics, the university food environment (UNI-FOOD, across six domains), circadian eating patterns, influencing factors, and anthropometric measurements. Data were analysed using SPSS version 27, employing descriptive statistics, chi-square tests, and univariable and multivariable binary logistic regression, with significance set at p < 0.05. Results The mean age of respondents was 20.03 {+/-} 2.58 years, and the majority were female (68.9%). Students generally perceived the university food environment as moderate, with affordability rated the weakest domain (mean 2.65 {+/-} 0.51) and food promotion/visibility the strongest (3.27 {+/-} 0.52). Most respondents (71.9%) exhibited moderate circadian eating patterns, while 21.2% had poor patterns. A significant association was found between the overall food environment and circadian eating patterns ({chi}2 = 44.369, p < 0.001). After adjustment, poor physical food accessibility (AOR = 6.44, 95% CI: 2.00-20.72, p = 0.002) and a poor food policy environment (AOR = 9.53, 95% CI: 3.51-25.87, p < 0.001) were independent predictors of poor circadian eating patterns. Circadian eating pattern was also significantly associated with BMI category ({chi}2 = 7.346, p = 0.025). Conclusion The university food environment, particularly physical accessibility and food policy, significantly influences circadian eating patterns among undergraduate students. Improving campus food accessibility and implementing supportive food policies may promote healthier meal timing and nutritional outcomes.