A cross-sectional study was conducted among 249 Chinese cancer patients with multiple diagnoses to validate a Chinese version of the Brief Fatigue Inventory (BFI-C). Cronbach's coefficient alpha was 0.92 for fatigue severity items and 0.90 for fatigue interference items. Construct validity was explored by principal factor analysis and suggested a two-factor solution: fatigue severity and fatigue interference. Internal consistency reliability was excellent. Convergent validity was examined by correlating the BFI-C with 2 subscales and 2 component scores of the MOS 36-Item Short-Form Health Survey (coefficients ranged between -0.44 and -0.71, P<0.001). Known-group validity was examined by comparing fatigue severity in patients having different scores on the Eastern Cooperative Oncology Group Performance Status Scale. Approximately 60% of patients experienced moderate to severe fatigue (4 or greater on the 0-10 scale of the BFI-C "fatigue worst" item). The BFI-C is a valid, reliable instrument to measure the severity and impact of cancer-related fatigue among Chinese patients.