The congenital deficit of protein C has a great diversity of clinical manifestations regarding age. In this paper, we describe the case of a man whose initial symptomatology appeared at the age of 68. Protein C is a vitamin-K dependent plasmatic glycoprotein which has anticoagulant activity through the inactivation of factors Va and VIIIa. The hereditary deficit of protein C is usually presented in a dominant autosomic mode with partial penetration and its prevalence is estimated in each of 200-300 healthy blood donors.