This cross-sectional study investigates the prevalence and risks for psychiatric diagnoses in a large cohort of children with Chiari malformation type 1 (CM1) presenting for neurosurgical evaluation. Children between the ages of 6 and 17 years who were evaluated and diagnosed with CM1 at a neurosurgery clinic were identified. Eighty-six participants were recruited for this study with an average age of 11 years. Parents of participants completed a pediatric medical history questionnaire and a semistructured interview regarding the child’s psychiatric, developmental, medical, and family history. A review of medical records was completed to complement interview data. Elevated rates of psychiatric diagnoses, including attention deficit hyperactivity disorder (ADHD) (22.1%), anxiety (12.8%), and depression (10.5%), were identified in the study population when compared to published norms in the general population documented by the American Psychiatric Association in 2013. In addition, elevated rates of psychiatric diagnoses in first-degree relatives of study participants were also identified. A 2-step binary logistic regression analysis revealed that maternal complications during pregnancy (Wald = 6.52, p = 0.01) increased the risk of a psychiatric diagnosis 9-fold. Premature birth (Wald = 6.79, p = 0.01) also significantly predicted a psychiatric diagnosis amongst participants. The current findings suggest a high prevalence of psychiatric illness in children with CM1. Pregnancy complications were associated with a high risk of a psychiatric diagnosis. Early CNS developmental disturbance may explain this relationship. Prematurity only slightly improved the prediction model. Limitations and future directions are discussed, including the cross-sectional nature of the present study, possible self-selection bias, and the importance of future investigation of other causative and/or associative factors of CM1, such as cognitive, psychiatric, and medical influences on health status.