Plasma protein-C exerts anticoagulatory effects by inactivating factors V and VIII. Hereditary protein C deficiency is transmitted as an autosomal dominant disorder. Homozygous individuals usually develop purpura fulminans as newborns; heterozygous protein C-deficient individuals are at increased risk for venous thrombosis and pulmonary embolism. However, arterial thrombosis occurring as a result of congenital protein-C deficiency is still controversial. We describe a young patient with heterozygous protein-C deficiency who experienced both pulmonary embolism as well as myocardial infarction due to thrombotic occlusion without underlying major risk factors. Acute myocardial infarction in young without underlying major risk factors may be evaluated for protein c deficiency.