Of the six types of dual coagulation factors deficiency, combined factors V and VIII are the most common type, a few cases of this disease have been reported in different populations. This accounts for the relatively low number of cases reported so far. Our report, which included 19 patients, is the second largest group that has been reported from one centre in north-eastern Iran. The most frequent spontaneous bleeding symptoms were epistaxis and haemarthrosis, and the most frequent traumatic bleeding symptoms were bleeding after dental extraction and bleeding after cutting any part of the body. It seemed that dual coagulation FV and FVIII deficiency is as severe as single coagulation factor (V or VIII) deficiency.