Abstract: 68 family members of patients with cerebrovascular diseases were selected, and their family function status were measured by Family APGAR index. The validity of the tool was evaluated though comparing family function status after and before onset of disease patients suffered. For evaluation reliability of t he tool,weighted Kappa w as calculated. T he results show that all Kappa(w) for APGAR and each component of the scales are above 017 ex cept Kappa(w) for adaptation, which is 015519. There are significant difference ( P<0101 for adaptation, partnership, gorwt h;and P<0105 for Affection and Resolve) between scores of APGAR after and befor e onset of disease. It is accepted w ith strong ev-idence that the reliability and v alidity of the tool is satisfied for evaluatingfamily function of patients with cerebr ovasular disease.