In order to determine what should be done for laryngeal cancer patients when surgical margins are positive, and to evaluate their prognosis, a retrospective review of 21 laryngeal cancer patients with positive surgical margins out of 714 surgically treated cases (2.9%) was carried out. Nineteen patients were treated with postoperative radiation therapy. Two patients who had had endolaryngeal partial laryngectomy were treated with vertical partial laryngectomy. Two patients were lost to follow-up. Ten patients (10/19; 53%) were recurrence-free. Four patients had local, two had regional, and two had locoregional recurrences. Only one patient with a local recurrence could be salvaged with total laryngectomy and is disease-free. One patient developed liver metastasis. Nineteen patients had a mean and median disease-free survival of 48 and 36 months, respectively. Nine out of fourteen patients (64%) treated curatively were recurrence-free. The patients with positive margins developed significantly more locoregional recurrences than those with free margins (P < 0.05). We conclude that surgical margins must be checked peroperatively with frozen sections to make sure that they are free. The margins of every laryngectomy specimen must be diligently examined. If positive, re-excision, postoperative radiotherapy and chemotherapy are treatment alternatives. They should not just be managed with close follow-up. However, whatever treatment is applied, the prognosis for patients with positive margins is significantly worse than for those with free margins.