A cross-sectional study was performed at the faculty of medicine, Zagazig University using Arabic translated Pittsburgh Sleep Quality Index (PSQ) questionnaire, and academic performance was assessed with a self-reported grade point average (GPA) in the last year. Results: A total of 278 fourth-year medical students were interviewed and had comprehensive data on demography, lifestyle, academic performance, and sleep quality. Poor sleep prevalence was 25.5%. There was a statistically significant difference among the poor sleepers’ group and good sleepers’ group regarding physical activity and (Grade point average) GPA. Conclusion: Poor sleep quality may adversely affect GPA as well, inducing a vicious cycle. Moreover, the sleep disturbances rate among medical students has to be a reason for intervention