Background: Childhood blindness and low vision have become major public health problems in developing countries. The purpose of this study was to categorise the causes of visual impairment according to aetiology and provide detailed local information on visually impaired children seeking low-vision services in a tertiary eye centre in Nepal. Methods: A retrospective study was conducted of all visually impaired children (visual acuity of less than 6/18 in the better eye), aged less than 17 years seen in the low-vision clinic at the Sagarmatha Chaudhary Eye Hospital in Lahan between January 1, 2012 and December 31, 2013. Results: Of the 558 visually impaired children, the majority were males, 356 (63.7 per cent). More than half (56.5 per cent) of the children were in the 11 to 16 years age group. Many of the low-vision children (52.9 per cent) were identified as having moderate visual impairment (visual acuity less than 6/18 to 6/60). Most children were diagnosed with childhood (36.2 per cent) or genetic (35.5 per cent) aetiology, followed by prenatal (22.2 per cent) and perinatal (6.1 per cent) aetiologies. Refractive error and amblyopia (20.1 per cent), retinitis pigmentosa (14.9 per cent) and macular dystrophy (13.4 per cent) were the most common causes of paediatric visual impairment. Nystagmus (50.0 per cent) was the most common cause of low vision in the one to five years age group, whereas refractive error and amblyopia were the major causes in the six to 10 and 11 to 16 years age group (17.6 and 22.9 per cent, respectively). Many of the children (86.0 per cent) were prescribed low-vision aids and 72.0 per cent of the low-vision aid users showed an improvement in visual acuity either at distance or near. Conclusion: Paediatric low vision has a negative impact on the quality of life in children. Data from this study indicate that knowledge about the local characteristics and aetiological categorisation of the causes of low vision are essential in tackling paediatric visual impairment. The findings also signify the importance of early intervention to ensure a better quality of life.