Neuronal ceroid lipofuscinoses are a group of rare neurodegenerative disorders that are characterised by an accumulation of autofluorescent lipopigments in neurons and extraneuronal tissues. We report on a 4-year-old boy who presented with an acute onset of seizures followed by rapid psychomotor deterioration, ataxia, and visual failure. Photic stimulation at 1 to 3 Hz elicited discrete spike and wave discharges in the electroencephalogram, which were diminished at a higher frequency of stimulation. The electroretinogram was extinct. Magnetic resonance imaging of the brain showed generalised cerebral and cerebellar atrophy. Electron microscopic examination of lymphocytes and samples of muscle and skin revealed characteristic curvilinear inclusion bodies. To our knowledge, this is the first case of late infantile neuronal ceroid lipofuscinosis to be reported in a Hong Kong Chinese patient.