Eight hundred samples of vaginal swabs were taken from women with active sexual life attending the Cervicouterine Cancer Opportune Detection Service at the Familial Medicine Unit No. 18 of the National Institute of Social Security, to study the incidence and prevalence of vaginal trichomoniasis, the presence of yeasts of the genus Candida and their relationships with clinical features of vulvovaginitis. Identification of parasites was made by means of direct examination with light microscope; 14.39 per cent of candida vulvovaginitis against 3.13 per cent of trichomoniasis was found; in only five cases the two parasites were associated. Leukorrhea and vaginal pruritus were the major symptoms found and the most affected anatomical regions were vaginal walls in trichomoniasis and cervix in candidiasis. Although vaginal trichomoniasis is a worldwide distributed parasitosis, its frequency is very variable, not so vaginal candidiasis, which is more frequent.