This study describes the stomatological findings reported on 20 Peruvian patients infected by the human AIDS virus. Lesions occurring most frequently were: xerostoma (80%), pseudomembranous candidiasis (70%), commissural cheilitis (55%), atrophy of filiform papillae (40%), ulcerative lesions (30%), vellous leucoplasia (25%) and erithematose or atrophic candidiasis (25%). Prevalence of the diverse lesions detected was correlated with the clinical stage of the disease in order to identify those manifestations that could be considered as early signs or precursors of the Acquired Immuno-Deficiency Syndrome (AIDS). The present article includes a review of the literature related to those clinical, epidemiological and preventive aspects that the dental surgeon must understand if he is to perform diagnosis and treatment on this type of patients.