Objective: To estimate the prevalence of Joubert syndrome (JS) in Italy applying standards of descriptive epidemiology, and to provide a molecular characterization of the described patients cohort. Methods: We enrolled all patients with a neuroradiologically confirmed diagnosis of JS and resident in Italy in 2018, and calculated age and sex prevalence, assuming a Poisson distribution. We also investigated the correlation between proband chronological age and age at diagnosis, and performed Next-Generation Sequencing (NGS) analysis on probands’ DNA when available. Results: We identified 284 JS patients: the overall, female- and male-specific population-based prevalence rates were 0.47 (95% CI 0.41-0.53), 0.41 (95% CI 0.32-0.49) and 0.53 (95% CI 0.45-0.61) per 100,000 population, respectively. When considering only patients in the age range from 0 to 19 years, the corresponding population-based prevalence rates rose to 1.7 (95% CI 1.49-1.97), 1.62 (95% CI 1.31-1.99) and 1.80 (95% CI 1.49-2.18) per 100,000 population. NGS analysis allowed identifying the genetic cause in 131 out of 219 screened probands. Age at diagnosis was available for 223 probands, with a mean of 6.67 ± 8.10 years, and showed a statistically significant linear relationship with chronological age (r2=0.79; p<0.001). Conclusions: We estimated for the first time the age and sex prevalence of JS in Italy, and investigated their genetic profile. The obtained population-based prevalence rate was approximately 10 times higher than that available in literature for children population.