BACKGROUND The aim of this study was to compare oxiconazole, 1 p. 100 cream, with ketoconazole, 2 p. 100 cream, applied once-daily, in the treatment of tinea cruris. METHODS A prospective, randomized, double-blind trial was performed in 8 dermatology departments on two parallel groups in patients having this type of mycosis confirmed by mycological examination. RESULTS The efficacy was analyzed in 66 out of the 79 patients included in the study (36 patients treated with oxiconazole, 30 with ketoconazole). At Day 14, a first assessment was made and 77.1 p. 100 of the patients treated with oxiconazole had been cured; this result was significantly better (p < 0.05) than that obtained with ketoconazole (51.7 p. 100 of cured patients). At Day 21, after a further week of treatment, both treatments were efficient with statistically non-different results between the two groups: 97.2 p. 100 of the patients treated with oxiconazole, versus 86.7 p. 100 with ketoconazole. Thus, a greater rapidity of action of oxiconazole was observed. No correlation was detected between the ratio of cured patients and the duration of the mycosis. The safety was assessed in 74 patients. No adverse effects were reported for the patients treated with oxiconazole, whereas 9 patients treated with ketoconazole experienced contact sensitization reactions and irritant skin reactions due to the application of the product. The difference between the two groups of treatment was statistically greatly significant (p < 0.001). Furthermore, acceptance of the drug on the part of the patient was better (p < 0.05) with oxiconazole. CONCLUSIONS After 3 weeks of topical treatment oxiconazole has revealed itself to be as efficient as ketoconazole, but it seems more rapidly efficient and better tolerated than ketoconazole.