Background: Childhood trauma has been associated with adult mental disorders, physical illness, and early death. The World Health Organization (WHO) supported the development of the Adverse Childhood Experiences International Questionnaire (ACE-IQ) to explore childhood trauma in adults. We report the psychometric properties of the Dutch version of the Adverse Childhood Experiences International Questionnaire 10 items version (ACE-IQ-10) in the Netherlands. Methods: Confirmatory factor analysis was performed in two convenience samples of consecutive patients presenting at an outpatient specialty mental health setting between May 2015 and September 2018: Sample A (N = 298), patients with anxiety and depressive disorders; and sample B (N = 234), patients with Somatic Symptom and Related Disorders (SSRD). Criterion validity of the scales of the ACE-IQ-10 was explored by their correlation with the PHQ-9, the GAD-7, and the SF-36. The correlation between reporting sexual abuse on the ACE-IQ-10 and in a face-to-face interview was assessed as well. Results: We found support for a two-factor structure in both samples: one for directly experiencing childhood abuse and another for household dysfunction, but also support for using the total score. The correlation between reporting a sexual trauma in childhood at face-to-face interview and the sexual abuse item of the ACE-IQ-10 was r = .98 (p < .001). Conclusions: The current study provides evidence on the factor structure, reliability, and validity of the Dutch ACE-IQ-10 in two Dutch clinical samples. It shows clear potential of the ACE-IQ-10 for further research and clinical use. Further studies are needed to assess the ACE-IQ-10 in the Dutch general population.