Objective To investigate the applicability of Bakes Caregiving Outcom Scale(BCOS) in the study of primary family caregivers'burden of stroke survivors. Methods The BCOS was used to inves-tigate the 180 primary family caregivers of stroke survivors.The applicability of BCOS was evaluated by in-ternal consistency,construct validity and criterion-related validity. Results The correlation coefficient be-tween the items and the total BCOS score was 0.408～0.725 (P ＜ 0.01 ).The total Cronbach's α was 0.877.Factor analysis used for examining the construct validity showed that 3 components were extracted and their accumulated contribution rate reached 60.93%.Factor loading of each item ranged from 0.510 to 0.875.The criterion-related validity was - 0.461 by using self-rated burden as a criterion(P ＜ 0.01 ). Conclusions BCOS is applicable in the evaluation of the primary family caregivers' burden of stroke survivors.