To evaluate the long-term quality of life of patients treated for head and neck cancer at a single institution in a developing country. Cross-sectional analysis of a consecutive series of patients. Tertiary cancer center hospital in Brazil. Eligible subjects included patients treated between 1974 and 1999 for head and neck carcinoma who had a minimum disease-free survival of 2 years and who completed a Portuguese version of the University of Washington Quality of Life (UW-QOL) questionnaire. Descriptive analyses of the results and comparisons of the scores for each UW-QOL domain, stratified by tumor site, were performed using nonparametric tests. Findings from 344 patients were analyzed. Of the study population, 140 (41%) had survived 2 to 5 years, 125 (36%) had survived 5 to 10 years, and 79 (23%) had survived more than 10 years since treatment. Primary tumor sites were in the oral cavity in 43.3% of cases, the oropharynx in 20.9%, the larynx in 32.0%, and the hypopharynx in 3.8%. In terms of treatment, 33.1% underwent surgery alone; 16.9%, radiotherapy alone; and 50% underwent combined treatment. Overall, 78.5% of the patients classified their own health as good or excellent. Stratified analysis showed that impairment in chewing and swallowing was more common in patients with oral and oropharyngeal tumors than in those with larynx and hypopharynx tumors, and speech impairment was more frequently related to patients with larynx and hypopharynx tumors than to those with oral and oropharynx tumors. In all tumor sites, the composite scores were significantly worse in advanced tumors than early stage tumors, but the use of combined treatment had the greatest negative impact on quality-of-life scores, after we adjusted for T and N stage with multivariable analyses (P<.001). The Portuguese version of the UW-QOL questionnaire was an effective tool to evaluate quality of life in a Brazilian population. Although many patients reported some limitations, most reported a good to excellent long-term quality of life.