Studying at medical universities involves a high academic workload, frequent movement between clinics, and, in some cases, employment in medical institutions. These factors may impair cognitive function and contribute to the development of anxiety, sleep disturbances, and daytime sleepiness.  This study aimed to assess the prevalence and severity of sleep disorders among medical university students in a megalopolis. We used the Epworth Sleepiness Scale (ESS) and the Spiegel Morningness–Eveningness Questionnaire (MOS-SS) to anonymously survey 1,627 students (1,329 females and 298 males) from all years and faculties at St. Petersburg Pediatric Medical University. It was found that 86.7% of students feel daytime sleepiness of varying severity, and it is much more common in females (96.0%) than in males (45.2%; p = 0.0000). Various sleep-quality disturbances were identified in 94.5% of students; girls had them more often (99.6%) than boys (71.9%; p < 0.0000). We found a moderate positive correlation between daytime sleepiness and sleep disorder severity (r = 0.45; p < 0.05). The study findings substantiate the need for preventive measures aimed at improving sleep quality and adjusting academic workload, as well as for specialist consultations in cases of severe sleep disorders.