Objective: Diabetic patients usually have co-morbidities requiring the use of multiple medications, making them more vulnerable in experiencing drug related problems (DRPs) that may affect their quality of life (QOL). The objective of this study was to asses DRP in type 2 diabetes (T2D) patients and factors associated with its occurrence and the DRPs that affect QoL. Methods: A cross-sectional study was conducted among T2D patients who were attending a tertiary care teaching hospital, Lebanon. The identification and assessment of DRPs were based on the Pharmaceutical Care Network Europe tool version 8.03. The QoL was assessed using Health Related Quality of Life Brief Clinical Inventory. Results: The total number of DRP was 313 with a mean of 2.05 ± 1.03 per patient. The most common DRPs encountered were adverse drug event (31.3%), untreated symptoms or indication ( 10.54%), effect of drug treatment not optimal (7.34%) and high drug dose (7.34%). Logistic regression showed that polypharmacy and several comorbidities such as stroke, dyslipidemia, heart failure, coronary artery disease, renal and liver impairment were common factors significantly associated with different types of DRPs (p<0.005). The risk of having problems” No effect of drug treatment”,” Effect of drug treatment not optimal” and “Adverse drug event (possibly) occurring” was significantly increased in patients with abnormal HbA1c. The use of sulfonylurea increases the risk of ” Inappropriate duplication of therapeutic group” (p= 0.047). Following a low sugar diet showed to decrease the probability of having problem” Patient uses/takes more drug than prescribed” by 99.99%. On the other hand, insulin administration showed to increase 7.63 times this probability (p=0.006). The average HRQoL was 40 ± 9.900. Linear regression showed that problems “Untreated indication and “Patient uses unnecessary drug” were associated with poor QoL score. Having a medical insurance was found to be associated with better HRQoL scores. Conclusion: Early identification of DRPs and factors associated with them are essential to pre- vent and resolve them in diabetic patients by engaging clinical pharmacist, which may ultimately improve patient’s QoL