The aim of this prospective study was to evaluate the effectiveness of fat injections in the treatment of velopharyngeal insufficiency (VPI). The study involved 10 patients (6 adults aged 19-48 years and 4 children aged 5-13 years) with mild/moderate VPI who were injected with 3.5 to 8 mL of fat in the posterior, lateral pharyngeal walls and soft palate under general anaesthesia. A second fat-grafting procedure was performed in 2 patients to achieve further improvement. Nasoendoscopy revealed a reduction in the closure gap in all patients, and the perceptual evaluation demonstrated improved speech intelligibility and resonance and reduced nasal air leakage in all cases (P < .005). The aerodynamic assessment showed a significant reduction in nasal airflow during phonation (P < .05). Follow-up was 6 to 23 months. In conclusion, fat injections improved voice resonance and reduced nasal air escape in all treated cases and can be a promising alternative to major procedures, such as velopharyngoplasties, for the treatment of mild/moderate VPI.