Factor VII or proconvertin is a vitamin K-dependent plasma glycoprotein synthesized by the liver. Factor VII deficiency is suspected with the combination of an elongated Quick time and a normal activated partial thromboplastin time. Constitutional deficits are very rare and have autosomal recessive transmission; they are also phenotypic ally and genotypic ally very heterogeneous. This case is about a child of first-degree relatives, who was admitted to pediatric emergencies for important epistaxis requiring transfusion. The biological assessment showed a normal partial thromboplastin time (TCK) with a low prothrombin level, suggesting a problem in the exogenous pathway of coagulation. The Factor VII assay showed a deficit evaluated at 2%. Screening was conducted among parents and siblings and revealed the presence of the deficit in all family members in various degrees, which adds to the singularity of this case.