Abstract Oculomotor nerve palsy was found in 28 children. Trauma was the cause in seven, infection in six. while tumour, poison and migraine were each responsible for one case. Twelve cases were cryptogenic: eight of these were present at birth (but three were probably due to birth trauma), and four cases appeared in infancy, but with no cause found even on full neuroradiological investigation. Among these 12 cases the pupil was large in only three, normal in four and small in five. Cyclic spasms were not seen in this series. Among the five congenital cases associated abnormalities including spina bifida, Goldenhar's syndrome and developmental delay were found in four. Acquired palsy does not seem to have a sinister significance.