Purpose: The aim of this study is to evaluate the clinical, demographic, and autoimmune characteristics of stuttering cases with and without Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections (PANDAS) comorbidity. Materials and Methods: The study included 271 children and adolescents aged 2-17 years who were brought to our outpatient clinic between 2012 and 2022 and diagnosed with stuttering. The demographic information and medical characteristics of the patients and their families, such as infections, allergies, rheumatic diseases, and tonsillectomy or penicillin prophylaxis, were evaluated retrospectively. Their routine laboratory test results were also documented. Results: In total, 55 girls (20.3%) and 216 (79.7%) boys at a mean age of 7.6±3.6 years were included. Forty-eight cases (17%) were in the PANDAS group, and 223 (82.3%) were in the non-PANDAS group. The comparison of the PANDAS and non-PANDAS groups showed that the PANDAS group had significantly higher rates of history of tonsillectomy, history of adenoidectomy, and history of frequent infections. The rates of psychiatric, autoimmune, and allergic diseases in the families of the cases in the PANDAS group were significantly higher. The PANDAS group had a significantly greater frequency of comorbid conditions such as obsessive-compulsive disorder, tics, attention-deficit/hyperactivity disorder, and anxiety, as well as a greater mean number of comorbid conditions with at least one diagnosis. Additionally, the age at onset of psychiatric symptoms and the mean age of cases were higher in the PANDAS group. The mean initial anti-streptolysin O level of the PANDAS group was 326.5±335.3 IU/mL, while the mean level in the non-PANDAS group was 155.6±215.1 IU/mL. Conclusion: Both the individuals in the PANDAS group and their families had high rates of comorbidities and inflammatory and autoimmune disorders. In cases of stuttering, there is a need to evaluate these conditions, determine the required methodologies, and explain the relevant pathophysiological mechanisms.