Gentamicin is an aminoglycoside antibiotic produced by Micromonospora echinospora. It is a bactericidal inhibitor of protein synthesis. It is generally used as a curative treatment in association with beta-lactam antibiotics. However, to guarantee therapeutic success, it is essential to use quality drugs in today’s context of substandard, adulterated and falsified multi-source essential drugs.The overall aim of this study was to assess the quality of injectable gentamicin sold in Bamako’s health centers and private pharmacies. 20 samples were analyzed and found to be non-compliant with the required specifications. The causes of non-conformity were either under-dosage of active ingredient, over-dosage of active ingredient and/or out-of-specification average volume or pH.The results clearly raise the question of the systematic registration of drugs before they are placed on the market.