Marjolin's ulcer is a rare and often aggressive cutaneous malignancy that arises in previously traumatized or chronically inflamed skin, particularly after burns. We reviewed 264 burns cases treated in our departments to assess the frequency and clinicopathological features of this malignant complication. We found 31 cases of Marjolin's ulcer and a further 14 cases of nonmalignant ulceration at previous burn sites. Eighteen Marjolin's ulcers were located on the extremities, six on the scalp, six on the trunk, and one on the nose. Most malignancies were squamous cell carcinomas. The average time lag between the burns and subsequent malignant ulceration was 19 years. Four of the malignant ulcers had spread to regional lymph nodes, but there were no distant metastases. This study emphasizes that Marjolin's ulcer should be considered as a significant postburn complication.