BACKGROUND: The northeastern region (NER) of India is geographically isolated and ethno-culturally different from the rest of the country. There is lacuna regarding the data on causes of blindness and severe visual impairment in children from this region. AIM: To determine the causes of severe visual impairment and blindness amongst children from schools for the blind in the four states of NER of India. DESIGN AND SETTING: Survey of children attending special education schools for the blind in the NER. MATERIALS AND METHODS: Blind and severely visually impaired children (best corrected visual acuity < 20/200 in the better eye, aged up to 16 years) underwent visual acuity estimation, external ocular examination, retinoscopy and fundoscopy. Refraction and low vision workup was done where indicated. World Health Organization's reporting form was used to code anatomical and etiological causes of visual loss. STATISTICAL ANALYSIS: Microsoft Excel Windows software with SPSS. RESULTS: A total of 376 students were examined of whom 258 fulfilled the eligibility criteria. The major anatomical causes of visual loss amongst the 258 were congenital anomalies (anophthalmos, microphthalmos) 93 (36.1%); corneal conditions (scarring, vitamin A deficiency) 94 (36.7%); cataract or aphakia 28 (10.9%), retinal disorders 15 (5.8%) and optic atrophy 14 (5.3%). Nearly half of the children were blind from conditions which were either preventable or treatable (48.5%). CONCLUSION: Nearly half the childhood blindness in the NER states of India is avoidable and Vitamin A deficiency forms an important component unlike other Indian states. More research and multisectorial effort is needed to tackle congenital anomalies.