The objective of the recent study was to determine the prevalence of poor sleep quality and to assess its psychological and general health correlates among secondary school students in the city of Assiut, Egypt. A cross sectional study was conducted among 829 secondary school students (selected by multistage stratified random sampling) aged 15–19 years in Assiut. Students filled in a self-administered questionnaire that included demographic data, Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale, general perception of health, and the short form of Depression Anxiety and Stress Scale. The prevalence of poor sleep quality (PSQI >5) was 72.5%. The mean PSQI score was 7.35 ± 2.94 standard deviation. Poor sleep quality was higher among females, urban residents and public school students. Correlates of poor sleep by multivariate analysis were age, urban residence, public education, mild to moderate and severe to very severe anxiety symptoms, severe to very severe depressive symptoms, excessive daytime sleepiness, and feeling fully active sometimes and not active at any time. Poor sleep quality was alarmingly highly prevalent among secondary school students, with significant health consequences. Increasing the awareness of the community especially adolescents, parents, and school teachers about healthy sleep is an essential priority.