The study aimed to develop a brief geriatric assessment (BGA) tool for the general practitioner to evaluate geriatric syndromes in community-dwelling older adults. A cross-sectional study. 58 communities from four aging cities in Taiwan. 1,258 community-dwelling older adults aged 65 years and above. The BGA targeted physical function impairment, cognitive impairment, and mood impairment. The cutoff values of physical function tests (handgrip strength and 6-meter walk test [6MWT]) were estimated by receiver operating characteristic analysis. Second, the diagnostic validity of the BGA was calculated in terms of sensitivity, specificity, and predictive values, which were compared to corresponding comprehensive geriatric assessment (CGA) items. Third, the associated risk factors of geriatric syndromes were selected using stepwise logistic regression. Finally, we combined items selected from literature and CGA and then proposed a practical BGA framework. The proposed BGA comprised dominant handgrip strength, 6MWT, self-report personal birthday, address, and telephone number, question 'Do you have depressive mood for the past two weeks?', Rinne tuning-fork tests, Snellen scale, and body mass index. It evaluated multidimensional aspects of geriatrics syndromes including physical, cognitive, mood, and sensory impairment, sarcopenia, and nutrition status. Sensitivities in the Taiwan BGA items ranged from 48% for dominant handgrip strength to 97.6% for 6MWT corresponding to physical impairment; 58.3% for cognitive impairment corresponding to Short Portable Mental Status Questionnaire; 62.7% for mood impairment corresponding to Geriatric Depression Scale. The Taiwan BGA for the general practitioner takes less than 10 minutes and is suitable in the community setting. Early management of geriatric syndromes in the community is important. The current study demonstrated a practical BGA tool for the general practitioner to comprehensively assess geriatric syndromes in community-dwelling older adults.