In Ethiopia, majority of the common leading causes of morbidity and mortality can be substantially reduced if essential drugs (EDs) are made available and appropriately used, where functioning of the pharmaceutical logistics system is necessary. Thus, tracking changes and improvements of the pharmaceutical logistics performance is important. The aim of this study was to assess the pharmaceutical logistics system of health centers (HCs) in Addis Ababa giving emphasis to non-program drugs (NPDs). A facility based descriptive cross sectional survey of the pharmacy of HCs in Addis Ababa was conducted using both quantitative and qualitative methods. Twenty four HCs were included in the study. Most 23(95.8%) of the HCs had their own Essential Drug List (EDL). All HCs determined their own NPDs resupply quantity, majority of them using standard formula. On average, only 47.52% of the HCs received the full quantity of NPTDs they ordered. It was the responsibility of all HCs to collect NPDs from Pharmaceutical Fund and Supply Agency (PFSA); majority 13(54%) of them using renting private vehicles. The availability of either of non-program tracer drugs (NPTDs) or tracer drugs from program source was 85.4%. Adequacy storage condition was 71.8%. Majority of the NPTDs had bin cards, and the accuracy in keeping stock records was < 10% for majority of NPTDs. Most 21(87.5%) of the HCs used computer system to manage NPDs. In 12 out of 22 HCs, not all personnel involved in handling of medicines waste were aware of the potential risks of hazardous medicines and 11(45.8%) of the HCs usually stored medicine wastes for 6 to 12 months. From the in-depth interview, all key informants (KIs) agreed that the strength of DTC determined the practice of selection. All the KIs related facilitators and barriers of forecasting and procurement with the services at PFSA. All KIs agreed that budget was determinant on availability of NPDs while the limited capacity of PFSA reported to contribute for the stock outs in HCs. Store X size was identified by all KIs as a facilitator and barrier for storage condition when it is large and small, respectively. The Health Commodity Management Information System was a major input for the Logistics Management Information System according to majority of the KIs. In conclusion, there was no major problem common to all HC’s regarding drug selection. Inadequate supply of NPDs at PFSA was a major obstacle for the overall logistics system. Transportation of NPDs and infrastructures related to medicine waste management were not adequate, Therefore, PFSA should enhance its capacity in all aspects. HCs’ management should support HCs’ pharmacy, and stakeholders should construct standard stores and medicine waste disposal sites. Key words: pharmaceutical logistics, non-program drugs, pharmaceutical storage, logistic management information system, medicine waste, LIAT