PROBLEM TO BE SOLVED: To facilitate attaching a wall surface greening unit to a structure without damaging mullion and transom bar.SOLUTION: A wall surface greening unit 2 which includes: solidification culture soil (planting base) 3 in which plant is planted； a mesh (planting base holding part) 4 holding the solidification culture soil 3 is installed along an outer wall surface of the structure 21 of a curtain wall structure method. In the structure 21, there are installed: a holding part material 24 which carries out holding of the mullion 22 of the structure 21； a vertical frame material 25 which is supported by the holding part material 24 and extends to a vertical direction along with the mullion 22； and a horizontal frame material 26 which horizontally extends between vertical frame materials 25 which adjoin horizontally, and is supported by the vertical frame material 25. The mesh 4 of the wall surface greening unit 2 is detachably attached to the horizontal frame material.
