Aim: To describe the rate of the controlled level of glycosylated hemoglobin (HbA1c) among diabetes mellitus patients in Dammam city, Kingdom of Saudi Arabia (KSA). To assess the association between the status of HbA1c and the different patient-related factors namely: insulin use, metformin, dyslipidemia, and statin use. Methods: This cross-sectional study was performed at Security Forces Hospital, Dammam, KSA, between November 2020 and February 2021. A sample of two hundred known diabetic patients who were regularly followed up at the outpatient department (OPD) was selected randomly for the current study. Results: A very low rate (24%) of controlled HbA1C levels in patients with diabetes (type 1 DM and type 2 DM), The data showed that 85 % of all participants in our study are T2DM patients, while only 15% are T1DM patients, Our data showed that patients with dyslipidemia, hypothyroidism, or hypertension have a high level of uncontrolled HbA1C levels. Surprisingly, both dyslipidemia and statin use were predictors of uncontrolled HbA1C, Unexpectedly, non-metformin use has a protective effect toward controlling HbA1C, While insulin use is a strong predictor of uncontrolled HbA1C (OD 5.20). Conclusion: A low rate of controlled glycated hemoglobin (HbA1c) level among patients with diabetes (T1DM and T2DM) in our sample urges the need for immediate intervention to investigate and improve the current findings. Further investigations are needed to fully explain the high rate of uncontrolled HbA1c among insulin, metformin and statins users. Keywords: Glycated hemoglobin, HbA1c, Diabetes mellitus, Statins, Metformin.