Medicinal plants are widely used in Africa, especially in rural areas, to meet primary health care needs. Among them Massularia acuminata (Rubiaceae) is mainly used for its aphrodisiac properties.In order to verify its acute toxicity, a single dose of 5000 mg/kg body weight (bw) of the ethanolic extract of the stems of this plant was administered to a group of 10 female rats. The control group, also consisting of 10 female rats, received only distilled water. During the 14 days observation, all clinical signs and deaths were reported. At the end of the study, the LD50, blood hematological and biochemical parameters, and hepatic and renal histological examination were performed.The results showed that the administration of the ethanolic extract of the stems of Massularia acuminata did not modify the behavior of the rats and the estimated LD50 was higher than 5000 mg/kg bw. The evaluation of hematological and biochemical parameters revealed a significant decrease (p <0.05) in the level of white blood cells and platelets, and a significant increase (p <0.05) in creatinine and total cholesterol. As for the histological study, apart from some hepatic apoptosis, the result did not show any hepatic and renal lesions.This study showed that the ethanolic extract of the stems of Massularia acuminata could exhibit hematotoxicity, nephrotoxicity and hepatotoxicity when higher doses were used.