Introduction: Joint hypermobility is a frequent syndrome in children and women, its impact on the musculoskeletal system are diverse and occur with different degrees of severity. Its consequences on vocal function have been studied sparingly, often preventing its optimal clinical approach. Objective: To describe the vocal behaviour of women with joint hypermobility syndrome. Material and method: A sample of 40 women with a medical diagnosis of joint hypermobility syndrome was studied. The assessment was carried out using video laryngeal stroboscopy, electroglottography, acoustic analysis, intensity and vocal overload tests. Results: In video laryngeal stroboscopy it was possible to demonstrate less muscle development, vibratory asymmetry and arytenoid imbalance. In the electroglottography, the CQ of the sample was 0.4 ± 0.05. The average maximum intensity was 85.8 ± 6.2 dB and the maximum phonatory time was 11.8 ± 3.1 s. In the tasks of the overload the sample showed rapid fatigability. Conclusions: The vocal behaviour of the subjects suffering from joint hypermobility syndrome implies glottic insufficiency, due to a lack of muscular development of the vocal folds.