Gaucher's disease, rare, hereditary and potentially mortal affection is characterized by the reduced concentration of the glucocerebroside lipid within the macrophage lysosomes. We report the case of a young 2 years old patient treated by transfusion since he was 9 months because of chronic anemia. According the clinical examination, the general state of the patients was bad ith important delayed stanturoponderal growth, a cutaneomucous paller and enormous splenomegaly. The blood count formula showed anemia with major thrombopenia. The myelogram was poor and the osteomedullar biopsy showed the presence of Gaucher's cells. The diagnosis has been confirmed by enzymatic dosage (Leucocytar b-glucosidase). The treatment of the patient has been substitutive enzymatic (inifucerase) with very favorable response. During Gaucher's disease, the enzymatic deficiency results in the pathologic accumulation of the substrate (glucocerebroside) in the lyososomes, this metabolic overloading may cause polyvisceral disease with spontaneous evolution ofter mortal. The recent discovery of a recombining glucocerebrosidase (imiglucerase) transformed the prognosis of this disease.