Introduction: Chiari malformations (CMs) are a heterogeneous group of disorders defined by anatomic anomalies of the cerebellum, brainstem, and craniovertebral junction (CVJ). This study aims to establish the demographic and clinical features, incidence, surgical procedures, and outcomes in large series of CMs, to investigate whether CM-0 is a subgroup of CM, Chiari 1 and 1.5 are different pathologies. Methods: In this study, all of the patients were evaluated and operated on for CM between 1985 and 2016. The patients were grouped into various subtypes. Demographic data, additional diseases, clinical features, surgical procedures, complications and outcomes were recorded. Results: In this study, 55 patients who underwent various surgical procedures were evaluated. Their mean age was 0.72±1.17. We detected 26 cases of CM-2 (47.3%), 16 cases of CM-3 (29.1%) and 13 cases of CM-4 (23.6%). When Chiari subtypes were compared, there were statistically significant differences in additional diseases , symptom duration, neuro examination, complication rate and hospital stay. Discussion and Conclusion: The findings obtained in this study suggest that the long hospital stay, the presence of SM and short symptom duration are associated with worse outcomes. The dura repair is the most important stage of surgery. Dural tear (CSF fistule) increases the complication rate and mean hospital stay and also causes the worse outcome. Therefore, the surgeon should spend more time on dura repair.