The study aims to evaluate the present stage of knowledge, attitudes, and behavior related to HIV/AIDS in the population of Rio de Janeiro's Rocinha slum, the target of a control program over the last 6 years. We interviewed two hundred and ten people of both sexes, ranging from 13 to 49 years of age, and the results were compared with those of a study conducted in 1990 with the same methodology and sample size. The analysis showed an association between single males and more preventive behavior. Misconceptions about the role of mosquito bites and blood donation in the transmission of HIV persist, almost in the same proportion. Comparing the two samples, there was a significant increase in the role of HIV/AIDS education provided by schools, and the study also identified an increase in the rates and regularity of condom use. More efforts should be made to reduce misconceptions about HIV transmission and the vulnerability of couples. The study also highlights the need for more consistent policies related to condom distribution to the general population.