Background: Cardiac risk factors and diseases have been linked to worse outcomes related to COVID-19 infection. The goal of treatment in such patients is targeting disease stabilization or regression. However, at any time this chronic disease can change to acute coronary syndrome (ACS) due to plaque rupture with either a precipitating factor or without. Objective: The aim of the current study was to detect the impact of COVID-19 infection on patients with chronic coronary artery disease. Patients and methods: A total of 102 patients with chronic coronary syndrome treated from May 2020 to September 2021 at Misr University of Science and Technology Hospitals were enrolled in our study. This cohort of patients was divided into two groups: Group 1 (COVID-19 Group) included patients with chronic coronary syndrome and being infected by COVID-19, while Group 2 (Control Group) included patients with chronic coronary syndrome without COVID-19 infection. Participants were followed up period of 6 months. Study outcomes were mortality and major adverse cardiovascular events (MACE) within 6 months follow up from COVID-19 diagnosis. Results: There were statistically significant increase in number of patients with unstable angina and non-ST-elevation myocardial infarction (NSTEMI) in the COVID-19 Group versus Control Group (54.8% versus 35%, respectively). As regard left ventricular (LV) dysfunction, congestive heart failure, percutaneous coronary intervention (PCI), coronary artery bypass graft surgery (CABG), ST-elevation myocardial infarction (STEMI), and death, these were more prominent in COVID-19 (Group 1) than in control group with chronic stable angina but without COVID-19 (Group 2) but without statistically significant difference. Conclusion: COVID-19 infection could have a direct worsening effect on coronary artery disease.