Factor XIII deficiency is a rare disorder of coagulation characteri-zed by moderate to severe bleeding tendency with increased susceptibility to intracranial hemorrhages, almost normal coagulation screening tests, clot lysis in 5 M urea solution & a tendency to abnormal wound healing. It is inherited as an autosomal recessive trait. However, acquired causes for its deficiency are rarely encountered. We describe here an inherited form of F XIII deficiency in two members (a boy & a girl) in a one family in Basrah.