This study investigated individual and incremental contributions of somatization and trait anxiety to pain report in children with pain-related functional gastrointestinal disorders. Eighty children (7–10 years) with pain-related functional gastrointestinal disorders completed the State-Trait Anxiety Inventory for Children, the Children’s Somatization Inventory, and 2-week pain diaries (assessing pain frequency and maximum pain). Hierarchical regressions indicated that both trait anxiety and somatization were significantly related to maximum pain and pain frequency, with somatization explaining more variance. Trait anxiety did not significantly add to prediction above somatization. Assessment of somatization may assist with treatment planning for children with functional abdominal pain.