The present study focuses on the quality control of quinine in the compressed pharmaceutical forms circulating in eastern Democratic Republic of Congo. The analyses performed on the collected samples included disintegration of the tablets, identification of quinine in the formulations by color reaction methods and thin-layer chromatography. The quantitative analysis was performed by spectrophotometric and volumetric methods. The most significantly observed findings were abnormalities of release; underdosing, overdosing and absence of the active ingredient, Which brings us to the conclusion that more than 30% of the samples analyzed are of inferior quality and adulterated.