Periodontal status was evaluatedin two cohorts participating in a study of the natural history of human immunodeficiency virus (HIV) infection. One cohort consisted of 77 seropositive and 44 seronegative homosexual men, and the other cohort was comprised of 44 seropositive and 39 seronegative parenteral drug users (PDU). No differences were observed between seropositive and seronegative individuals within a cohort in terms of clinical periodontal” parameters (percent of sites with ≥4 mm probing depth, percent of sites exhibiting bleeding on probing, mean oral hygiene index). The PDU displayed more existing periodontal disease than the homosexual men. Periodontal disease in the seropositive individuals in both cohorts was not strictly related to the number of CD4+ lymphocytes. Linear gingival erythema (LGE), defined as an erythematous band of at least 2 mm extending between adjacent papilla, was observed in all 4 groups. Seropositive homosexual men displayed more LGE than seronegative homosexual men (16.6% vs. 11.4%) and seronegative PDU displayed more LGE than seropositive PDU (38.5% vs. 29.5%), but neither difference was significant. LGE tended to be related to reduced numbers of CD4+ lymphocytes, but this relationship did not reach statistical significance. A statistically‐significant relationship was found between the presence of intraoral candidiasis and LGE in seropositive homosexual men: 42.9% of these subjects with candidiasis had LGE, while only 12.7% of the subjects without candidiasis had LGE (P<.05). For the seropositive PDU, 35.3% of the individuals with candidiasis had LGE and 25.9% of the subjects without candidiasis displayed LGE, but the difference was not statistically significant. Analysis of clinical parameters suggested that the very poor oral hygiene in the seropositive PDU may have obscured the candidiasis‐LGE relationship. Lastly, the incidence of necrotizing ulcerative gingivitis (NUG) and necrotizing ulcerative periodontitis (NUP) was low. For homosexual men 5.2% of seropositive individuals and none of the seronegative individuals displayed NUG. For the PDU, none of the seropositive individuals but 5.1% of the seronegative individuals displayed NUG. NUP was not detected in either cohort. These data indicate that there are differences in non‐HIV associated periodontal disease between homosexual men and PDU, regardless of serostatus. In addition, we observed an association between the presence of intraoral candidiasis and LGE in seropositive homosexual men. Lastly, the prevalence of necrotic gingival/periodontal lesions in seropositive individuals was low.J Periodontol 1995;66:30‐37.