Background: The Voice communicates a speaker's social standing, psychological attributes, and emotional state. Obesity is a health problem that has an impact on several bodily functions. By producing abnormal fat deposition in the abdomen and upper airways, obesity alters voice qualities.Objectives: In this study, We assess the impact of bariatric surgery on patients' voices who are morbidly obese.Patients and Methods: In this prospective, longitudinal study, 50 patients with planned bariatric surgery were examined pre-operatively and 6 months after surgery. The preoperative evaluation included Body Mass Index, Neck Circumference, Auditory Perceptual Assessment (APA), Voice Handicap Index (VHI) questionniare, laryngoscopic examination and acoustic analysis. Six months after surgery, patients were re-evaluated using the same pre-surgical data collection methods.Results: This study's findings revealed statistically significant differences in phonasthenia and almost of acoustic parameters mainly jitter, harmonic to noise ratio and maximum phonation time. Furthermore, there were significant differences in the voice handicap index.Conclusion: It is possible to conclude that an individual suffering from morbid obesity has significantly different vocal features. This study suggests that successful weight loss after bariatric surgery may influence voice acoustic characteristics.