Background: To evaluate the efficacy of topical mitomycin C (MMC) for the treatment of conjunctival tumor in a prospective design. Methods: Nine patients ( nine eyes) with conjunctival tumor were studied. The patients received topical MMC 0.04% four times daily by one to six courses. Each course consisted of medication for consecutive 7 days followed by 1 week without medication. Follow-up was conducted on patients for control of disease, and side effects. Results: In 7 patients, the tumor completely disappeared during the mean follow-up period of 24.57 +/- 8 5.94 months (range 18-35 months) with no recurrence. In 1 patient, there was no regression of the tumor, and in 1 patient cessation of the treatment was needed because of an adverse effect of the drug. Conclusion: Topical MMC is effective for the treatment of conjunctival tumor. Longer follow-up and large series are needed to assess the duration of tumor control. Copyright (c) 2007 S. Karger AG, Basel.