Background. Mandibular resection for oral cancer is often necessary to achieve an adequate margin of tumor clearance. Segmental mandibulectomy has been associated with a poor health-related quality of life (HRQOL), particularly before composite free tissue transfer to reconstruct the defect. Little is published in the literature contrasting the subjective deficit of segmental compared with rim resection. The aim of this study was to use a validated head and neck HRQOL questionnaire to compare rim and segmental mandibular resection in patients having primary surgery for oral cancer. Method. There were 224 consecutive patients between 1995 and 1999 who were treated by primary surgery for oral squamous cell carcinoma. One hundred twenty-tree had no mandibular resection, 44 had a rim resection, and 57 had a segmental resection. The University of Washington Quality of life questionnaire (UW-QOL) was adminstered before treatment, at 6 months, 12 months and after 18 months. Results. Preoperatively, patients undergoing segmental resection reported significantly more pain, chewing problems, and a lower composite UW-QOL score. Postperatively, the segment group tended to score worse at all time points, particularly in appearance, swallowing, recreation, and chewing; however, the difference between rim and segment was only seen in smaller resections without adjuvant radiotherapy. Little difference was seen between rim or segment for tumors <4 cm with radiotherapy and between rim and segments for tumors >4cm. Conclusion: After segmental mandibulectomy and reconstruction using composite free tissue transfer, the UW-QOL scores were relatively good. The only 2 difference between rim and segments was noted in the small resections without radiotherapy, and some of this was reflected in differences at baseline.