This study investigated the prevalence of Brucella antibodies in the general population in two regions in southern Italy. A total of 1,294 subjects were recruited from January to June 1996 among patients attending randomly selected public and private laboratories and pediatric outpatient clinics. Information on sex, age, residence, and occupation was recorded. Seroprevalence of brucellosis was studied by the safranin O-stained antigen microagglutination test. The chi-square test and multiple logistic regression were performed. An overall prevalence of brucellosis of 3.1% was recorded; no significant difference was found between the two regions, with values of 2.7% in Campania and 3.8% in Calabria. Multiple logistic regression analysis indicated that positivity to brucellosis was significantly associated with the province the subjects reside in, ranging from 0 in Salerno to 6.2% in Caserta, and that it significantly increased with age, ranging from 1% in persons under 16 to 4.2% in those over 65 (OR = 1.7; 95% CI = 1.04-2.6), whereas it was not significantly associated with sex. When analysis was conducted after restriction to subjects reporting to be working, occupation was found not to be significantly associated with brucellosis. Since the spread of the disease is still of concern, though circulation of Brucella is decreasing, strict application of measures for the eradication of brucellosis from livestock, pasteurization of milk and dairy products, and education regarding eating habits must be pursued.