Adolescents born before 33 weeks' gestation have reduced cerebellar volume compared with term-born controls, and this is related to their cognitive performance. We wished to determine whether this relationship is regionally specific. We measured midline and lateral cerebellar volumes in magnetic resonance imaging scans from 67 very preterm adolescents and 50 term-born controls at 14-15 years. Volumes of vermis and lateral lobes were reduced in the preterm group, after controlling for whole-brain volume. Lateral cerebellar volume decrease was associated with reduced cerebral white matter volume, and with reduced executive, visuo-spatial and language function. Vermis volume was less strongly related to cognitive function. Volume decrement of the lateral lobes, rather than the vermis, is associated with neuropsychological dysfunction in very preterm individuals.