Post traumatic renal artery thrombosis is rarely described in the literature. This pathology can result from stretch injury to inelastic intima of the renal artery, or by the direct flow to the abdomen causing compression injury to the renal artery against the vertebral column. However, the association of this pathology with hematologic diseases (in particular protein C deficit) was never described. We report an observation of a 28-year-old man with an uneventful history who was admitted to the intensive care unit for traumatic head injury associated with post traumatic renal artery thrombosis requiring nephrectomy. The etiologic investigation of this thrombo-embolic complication reveals a protein C deficit. Our patient was improved under treatment. This original observation confirms that post traumatic renal artery thrombosis can be associated with hematologic diseases (in particular protein C deficit).