The permanent disappearance of glottic closure eventually causes inadequate defecatory propulsion resulting in functional constipation. The aim of this study is to reveal functional constipation probably induced by lack of glottic closure in laryngectomized patients. The study was conducted in a prospective, tertiary care center. Forty patients who had undergone total laryngectomy (study group) and 30 who had undergone microlaryngoscopic surgery (control group) were evaluated. Based on the European Organisation for Research and Treatment of Cancer, Quality of Life Questionnaires C30, the presence of functional constipation was investigated using the Rome II diagnostic criteria and was confirmed by measurement of colonic transit time using a radiopaque marker test. Functional constipation and colonic transit time were found to be increased and statistically significant in laryngectomized patients (70 %) compared with the control group (26 %) (p < 0.01). Functional constipation is more prevalent among laryngectomized patients. When evaluating quality of life of patients undergoing laryngectomy, colorectal functions must be taken into consideration.