This paper measured senior high school students' level of sleep quality and psychological well-being in a private university in the Philippines. This study utilized the descriptive - correlational research design. A stratified random sampling technique selected the 328 senior high school students. The data were collected using two standardized psychological instruments: the Pittsburgh Sleep Quality Index (PSQI) and Ryff's Scale of Psychological Well-Being (RPSWB), analyzed through descriptive and inferential statistics. The findings revealed a poor sleep quality and a moderate level of psychological well-being of senior high school students. Pearson product-moment correlation yielded a significant relationship between sleep quality and sex, year level, and academic strand; a significant relationship between psychological well-being and academic strand; and no significant relationship between sleep quality and psychological well-being. To conclude, students can attain a good level of psychological well-being despite poor sleep quality. Collaborative efforts of guidance counselors, school administrators, and teachers may help the senior high school students educate and develop their sleep hygiene practices.