Background: Patients with post-COVID-19 syndrome continue to have symptoms related to COVID-19 after the acute phase infection, which require adherence to therapeutic regimen to improve self-efficacy. Aim of the study: Was to assess relation between self- efficacy and adherence to therapeutic regimen among patients with post Covid-19 syndrome. Research design: A descriptive correlation design was utilized. Setting: The study was conducted at Chest Outpatient Clinic at El-Demerdash Hospital Affiliated to Ain Shams University Hospital. Subjects: A convenience sample of all available patients (no= 133). Tools: Three tools were used in the current study: Patients' demographic characteristics, Self-Efficacy Survey and Therapeutic regimen adherence tool. Results: Revealed that 42.1% of patients under the study had high level of self-efficacy & 44.4% of them had high adherence level to the therapeutic regimen Conclusion: It can be concluded that there was highly positive significant correlation between total  levels of self-efficacy and adherence to the therapeutic regimen among the studied patients with post Covid-19 syndrome. Recommendation: Developing health educational program for the patients with post Covid-19 syndrome based on their needs to improve their awareness, self-efficacy and adherence levels to therapeutic regimen.