Cystic lymphoepithelial lesions of salivary glands (CLLSG) are nodular or diffuse salivary gland enlargements that are observed in patients who tested positive for human immunodeficiency virus type 1 (HIV-1). Two cases of CLLSG are reported. Particular emphasis is placed on the presence of HIV-1 major-core protein (P24), HIV-1 RNA sequences, Epstein-Barr virus (EBV) DNA sequences, and lymphocyte receptor gene rearrangement. Lymphoid alterations consisted of explosive hyperplasia with a prominent follicular reticular dendritic cell (DRC) network and numerous intrafollicular CD8+ lymphocytes. Intrafollicular DRC strongly expressed HIV-1 major-core protein and HIV-1 RNA, indicating that most DRCs actively replicated the HIV-1 virus. The presence of active HIV-1 replication within DRC and the absence of clonal EBV infected lymphoid population strongly suggest that CLLSG pathogenesis is primarily induced by HIV-1. The presence of oligoclonal immunoglobulin gene rearrangements in our cases, however, suggest the need of long-term follow-up of such patients to determine whether CLLSG could be a benign prelymphomatous disease.