Abstract. Green roofs are technology for establishing plants on the rooftops of building. Intensive systems are roof gardens, extensive systems are flat grass. Several examples of this technology can be found in Latvia. Green roof has many ecological and financial benefits – most important in case of Latvia are air pollution reduction, buildings energy demand decrease, acoustic insulation of building, heat island effect reduction locally and in the level of city, habitat creation for plants and animals in the city centre, landscape architecture solutions. In this paper green roof impact on buildings energy efficiency is studied. Green roof cannot be regarded only as additional insulation layer, practically energy demand decrease is insignificant to justify the green roof implementation. Therefore other benefits must be taken into account.