Greening system and construction method thereof

The invention provides a greening system and a construction method thereof, wherein the greening system is easy to construct by using a container unit easy to process and has excellent water resistance, water-retaining property, heat insulation property and load resistance. A greening system for growing plants, the greening system comprising: a soil layer for planting plants; a water-permeable soil layer support part for supporting the soil layer; and a water container part that supports the soil layer and the soil layer support part and has a water storage part and an air layer on the upper side thereof, the water container part being configured such that the container units are formed in a substantially rectangular shape in a top view, and the sides of the adjacent container units are fitted to each other to have the water storage part. The container unit is provided with at least two container-shaped parts in a manner of connecting the at least two container-shaped parts which can be used as water containe