Objective To evaluate the tonsils as a source of halitosis and to assess the efficacy of laser CO2 cryptolysis for the treatment of oral bad breath caused by chronic fetid tonsillitis. Methods Fifty-three patients with halitosis originating from chronic fetid tonsillitis, who completed laser cryptolysis were enrolled in the study. The origin of halitosis was demonstrated by Finkelstein's tonsil smelling test, which included massaging the tonsils and smelling the squeezed discharge. All patients were treated by laser cryptolysis, an office procedure done under topical anesthesia. Subjective and objective postoperative assessment was based on self-and-family report and clinical assessment. Patients were reexamined 4 to 6 weeks post-treatment, and when the need for further laser treatment was determined. Results Complete elimination of halitosis required one session in 28 patients (52.8%), 2 sessions in 18 patients (34%), and 3 sessions in 5 patients (9.4%). Follow-up period ranged from 3 to 36 months (mean, 20.8 ± 8.5 months). No adverse effects or complications were encountered. Conclusions After excluding dental or periodontal, sinonasal, oral, pulmonary, or gastroenterological diseases as the origin of halitosis, chronic fetid tonsillitis remains a common cause of halitosis. Patients suffering from halitosis should be treated relying on their examination including Finkelstein's tonsil smelling test. Laser CO2 cryptolysis is an effective, safe, and well-tolerated procedure for the treatment of halitosis.