Four cases of conjunctival papilloma in two different patients were examined by in situ hybridization for HPV DNA type 6/11, 16/18 and 31/33/51. Formalin-fixed and paraffin-embedded tissues were hybridized by biotinylated probes. One tumor and one of its recurrences showed nuclear positivity for HPV 6/11 in the superficial cells of the epithelium. The results suggest that HPV type 6/11 may be etiologic agent of conjunctival papillomas. The benign behavior of these neoplasms may be related to the etiologic role of this type of HPV.