Objectives: To assess the quality of INR control in Egyptian patients who are on warfarin therapy through calculating the TTR and study different variables affecting INR control in those patients. Methods: A Retrospective cohort study conducted in Cardiology Department, Zagazig University Hospitals, from December 2018 to August 2019. It included 250 patients who were prescribed Warfarin therapy for different indications. Results: After calculating TTR of each patient the level of anticoagulation control was determined using the following cut off values: a) Good control: TTR>70%, b) Intermediate control: TTR 50 -70 %, c) Poor control: TTR <50%. Majority of patients 62% had poor control with TTR less than 50% and 17.20% had Intermediate control with TTR 50-70%. Patients with good TTR control represented 20.8%. Conclusion: Majority of Egyptian patients have poor anticoagulation control by means of TTR. Male gender, higher education and employment status are associated with higher mean TTR and better anticoagulation control. Male gender and employment were significant predictors for good INR control