This study aims to define cut-off points for the waist:hips girth ratio (WHR), using arterial hypertension as the outcome. The data refer to 3,282 individuals over twenty years of age examined in a survey conducted in the municipality of Rio de Janeiro in 1995-1996, using a two-stage sample. Sixty census tracts were drawn initially; subsequently, 34 households were selected systematically from each tract. Stature, weight, waist and hips girths, and blood pressure were measured in the households. The criterion for hypertension was a systolic blood pressure of 140 mmHg or diastolic pressure of 90 mmHg, or use of medication to reduce blood pressure. The sensitivity and specificity of different cut-off points for WHR were calculated in the prediction of arterial hypertension according to sex, age, and presence of overweight, classified according to World Health Organization guidelines. The best cut-off points for WHR were 0.95 for men and 0.80 for women. Compared to the waist:stature ratio and waist circumference, the WHR proved more capable of predicting arterial hypertension and less correlated with body mass index.