Research suggests that people with first-episode psychosis (FEP) report more childhood traumas and have lower metacognitive abilities than non-clinical controls. Childhood trauma negatively affects metacognitive development in population studies, while the association remains largely unexplored in FEP populations. Metacognition refers to the identification of thoughts and feelings and the formation of complex ideas about oneself and others. This study hypothesized that childhood trauma would be associated with lower metacognitive abilities in people with FEP. In a representative sample of 92 persons with non-affective FEP, we assessed childhood trauma, metacognitive abilities and symptoms of psychosis. We used the Childhood Trauma Questionnaire (CTQ) and the Metacognitive Assessment Scale––Abbreviated which includes Self-reflectivity, Awareness of the Mind of the Other, Decentration and Mastery. Hierarchical regression analyses were performed with metacognitive domains as outcome variables and childhood traumas as independent variables, while controlling for age, gender, first-degree psychiatric illness and negative symptoms. We found few significant associations between the different types of childhood trauma and metacognitive domains, and they suggested childhood trauma are associated with better metacognitive abilities. Study limitations included the cross-sectional design and use of self-report measures. Future studies could preferably be prospective and include different measures of psychopathology and neuropsychology.