Abstract. For high-density urban environments, vertical greenery is often employed as one of feasible alternatives of environmental improvement. Vertical greenery systems (VGS) are being served as an interesting measure to improve the quality of life and urban environments, but only a few studies have examined overall performance of VGS. Vertical greenery has potential benefits, including reducing the surface temperature of buildings facades and diurnal temperature fluctuation, alleviating Urban Heat Island and noise pollution, reducing g heat flux to the building and energy cost, transforming the urban landscape and enhancing visual effect and so on. This paper provides a literature review for VGS studying, including VGS classification and their effects on acoustic insulation, thermal, air flow and temperature, energy performance, CO 2 sequestration and microclimatic layer.