The assessment of quality of life (QOL) is an important part of cachexia management for cancer patients. Functional assessment of anorexia-cachexia therapy (FAACT), a specific QOL instrument for cachexia patients, has not been validated in Chinese population. The aim of this study was to validate the FAACT scale in Chinese cancer patients for its future use. Eligible cancer patients were included in our study. Patients' demographic and clinical characteristics were collected from the electronic medical records. Patients were asked to complete the Chinese version of FAACT scale and the MD Anderson symptom inventory (MDASI), and then the reliability and validity were analyzed. A total of 285 patients were enrolled in our study, data of 241 patients were evaluated. Coefficients of Cronbach's alpha, test-retest and split-half analyses were all greater than 0.8, which indicated an excellent reliability for FAACT scale. In item-subscale correlation analysis and factor analysis, good construct validity for FAACT scale was found. The correlation between FAACT and MDASI interference subscale showed reasonable criterion-related validity, and for further clinical validation, the FAACT scale showed excellent discriminative validity for distinguishing patients in different cachexia status and in different performance status. The Chinese version of FAACT scale has good reliability and validity and is suitable for measuring QOL of cachexia patients in Chinese population.