To explore associations between psychiatric symptoms and cerebral magnetic resonance imaging abnormalities in low-birth-weight adolescents, 55 very low-birth-weight (<or=1500 gm), 54 term small for gestational age (birth weight <10th centile) and 66 term control adolescents (birth weight >or=10th centile) were assessed at 14-15 years of age. Outcome measures were Schedule for Affective Disorders and Schizophrenia for School-Age Children, Attention-Deficit/Hyperactivity Disorder Rating Scale IV, Autism Spectrum Screening Questionnaire, and qualitatively assessed cerebral magnetic resonance images. The very low-birth-weight group manifested increased prevalence of psychiatric symptoms and disorders compared with controls (P < 0.001), especially symptoms of attention-deficit/hyperactivity disorder, and high frequency of ventricular dilatation, white matter reduction, thinning of corpus callosum, and gliosis (P < 0.01 vs controls). The Attention-Deficit/Hyperactivity Disorder Rating Scale score was significantly associated with white matter reduction and thinning of corpus callosum in this group. The term small for gestational age group had increased prevalence of psychiatric symptoms compared with control subjects, but not more frequent abnormalities on cerebral magnetic resonance imaging. In conclusion, attention-deficit/hyperactivity disorder symptoms were significantly associated with white matter reduction and thinning of corpus callosum in very low-birth-weight adolescents. No associations were found for other psychiatric symptoms and brain abnormalities in any of the groups.