The role of fibrin stabilizing factor is very important, which takes part in the last stage of clot formation and makes the clot strong and stable. People lacking this factor have high risk of uncontrollable bleeding after injury or surgery despite normal coagulation tests: APTT, PT, Fibrinogen, bleeding time and platelet function. Congenital factor XIII deficiency is rare which is caused by mutation of genes responsible for factor XIII synthesis at chromosome 1 and chromosome 6, with injury related symtoms of the large joints, muscular or intracranial bleeding. If diagnosed soon, patients can be treated effectively by CRYO or fresh frozen plasma. This is a case lacking activity of factor XIII from Bach Mai Hospital in which the authors want to attract more attention about this rare disease which needs timely diagnosis, consultation and proper treatment to prevent patients from complications such as muscular malnutrition and joints deformation due to repeated bleeding.