Serology is the primary means for identifying patients with HIV infection and Acquired Immunodeficiency Syndrome (AIDS). Testing of serum by serologic methods has been extensively used since 1985, not only for clinical diagnosis but also for epidemiological surveillance and donor screening in blood banks. Fast serological diagnostic techniques are now being developed, using urine and oral fluid, as an alternative for anti-HIV antibody screening, and many parallel studies are proving its accuracy. The purpose of this study was to evaluate the sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) of the ImmunoComb II HIV 1&2 Saliva((R)) test from Orgenics (Dot-ELISA) compared to the routine exams (ELISA and Western Blot) of HIV positive/AIDS patients, undergoing antiretroviral treatment or not, in different stages of the disease's evolution, and compared to serologic testing of known HIV negative patients by the use of serum ELISA (blood donors). To accomplish this, patients of the Immunogenic Deficiencies Control Center (CCDI) and voluntary blood donors of the Blood Bank Center of the Medical School of Sã:o Paulo/Federal University of São Paulo (EPM-UN I FESP) were evaluated. Sensitivity of Dot-ELISA in oral fluid was 100%, specificity 97.08%, PPV 96.66% and NPV 100%. The method used in this case study was shown to be highly sensitive and specific, being useful particularly in epidemiological surveillance and screening.