Background: Self-acupressure is a significant non-pharmacological modality, which is effective in improving sleep quality. Aim: This study aimed to evaluate the efficiency of self-acupressure techniques on quality of sleep among patients with Acute Coronary Syndrome (ACS). Design: A quasi-experimental design was used. Subjects: A purposive sample of 60 patients with ACS, divided into two groups (30 patients for each). Setting: This study was established in two Cardiac Care Units (CCUs), affiliated in Zagazig University Hospitals. Tools: A Structured Patients' Interview Questionnaire, Patients' Practice Observational Checklists Regarding Self-Acupressure Techniques, and the Geroningen Sleep Quality Scale. Results: The study group patients showed a marked increase in knowledge scores post-intervention compared to the control group. There were highly statistically significant improvements in patients' practices regarding self- acupressure techniques in the study group on post-intervention days 1, 2, and 3 compared to control group (p < 0.01). Patients in the study group exhibited significant improvements in quality of sleep, with highly statistically significant differences compared to the control group on post-intervention days 1, 2, and 3 (p < 0.01). A highly statistically significant strong negative correlation was found between self-acupressure practices and quality of sleep among patients in the study group on post-intervention days 1, 2, and 3 (p < 0.01). Conclusion: Self-acupressure intervention had a statistically significant positive effect on enhancing patients' knowledge and practice, which subsequently improved quality of sleep among patients with acute coronary syndrome. Recommendations: Self-acupressure techniques should be incorporated into the routine care of ACS patients in CCUs to effectively manage sleep disturbances. Key Words: Acute Coronary Syndrome, Quality of Sleep, and Self -Acupressure.