OBJECTIVE:To assess the spatial pattern of tuberculosis incidence in relation to the AIDS epidemic, with the aim of investigating the geographical influence on causality. METHODS:All AIDS cases from State of São Paulo, notified to the Brazilian Ministry of Health between 1991 and 2001, were included. The cases were stratified by municipality, by administrative health regions, AIDS transmission categories, gender and years since diagnosis. A Gaussian geostatistical model was used to construct a thematic risk map, utilizing the tuberculosis incidence among AIDS cases as the response variable. RESULTS:Exploratory analysis showed two patterns of AIDS incidence: one for the state capital, and another, with increasing risk, for the other municipalities. The more populous regions presented higher risk of tuberculosis transmission, with a pattern that matched the land occupation pattern, from east to west. The health regions with the highest AIDS incidence coefficients (per 10,000 inhabitants) were Santos (53.5), São José do Rio Preto (43.1), Ribeirão Preto (42.4) and São Paulo (40.3). The health regions with greatest tuberculosis incidence among AIDS cases were Santos (44.9%), Franco da Rocha (39.9%), Osasco (39.6%) and São Paulo (38.9%). CONCLUSIONS:The results allow the conclusion that geographical coordinates presented an association with tuberculosis risk, but not with AIDS risk.