The aim of this study was to determine whether subjective sleep quality was reduced in medical students, and whether demographics and sleep hygiene behaviors were associated with sleep quality. A Web-based survey was completed by 314 medical students, containing questions about demographics, sleep habits, exercise habits, caffeine, tobacco and alcohol use, and subjective sleep quality (using the Pittsburgh Sleep Quality Index). Correlation and regression analyses tested for associations among demographics, sleep hygiene behaviors, and sleep quality. As hypothesized, medical students’ sleep quality was significantly worse than a healthy adult normative sample (t = 5.13, p < .001). Poor sleep quality in medical students was predicted by several demographic and sleep hygiene variables, and future research directions are proposed.