Systemic mastocytosis is an uncommon disorder due to multiorgan infiltration by mast cells. The authors report the case of a man whose mastocytosis was revealed in an unusual way by hepatomegaly and portal hypertension of the sinusoidal type. This case was also characterized by the absence of urticaria pigmentosa, the presence of seborrheic warts in which mast cell infiltration was noted and the absence of digestive symptoms. The peculiarities of this case are compared to the published data.