Vernacular architecture based on bioclimatism concepts was developed and used through the centuries by many civilizations across the world. Different civilizations have produced their own architectural styles based on the local conditions. This study is carried out on the vernacular buildings of north-east India across all the bioclimatic zones. A survey of 42 houses, more than 70 years old was carried out at representative locations across all bioclimatic zones. The study has yielded findings relating bioclimatism, socio-economic status and cultural setup to the vernacular architecture of the region. Also, different solar passive features are available in most of these houses, related to temperature control and promoting natural ventilation. These houses are constructed using locally available materials like wood, cane, bamboo, stone, mud, jute, lime and represent unique examples towards sustainable building design.