A Portuguese version of the CAGE alcoholism screening test was administered to 68 alcoholic and 46 non-alcoholic male inpatients in a Psychiatric Hospital in São Paulo. The Portuguese text of the 14 questions, 4 of which were CAGE questions, is provided. When a score of two positive responses to any of the 4 CAGE questions was taken as a positive test result, the sensitivity of the test was 88% and the specificity was 83%. Increasing the cut-off point to 3 positive responses decreased the sensitivity to 81% and increased the specificity to 94%. The importance of cut-off points is discussed. The similarity between our data and results obtained with the English language CAGE test in other countries suggests that the CAGE questionnaire could be a useful tool for screening alcoholics in Brazil. The need for further validation studies in non-hospital populations is discussed.