An ecological greening wall and a construction method thereof are provided. The ecological greening wall comprises a plurality of fixed poles (2) arranged at intervals on the ground (1), and a reinforcement (3) with openings is fixedly connected between the fixed poles (2) and arranged along the fixed poles (2) in a vertical direction. Stacked vegetation bags (4) for greening are provided on at least one side of the reinforcement (3), and each includes a breathable and permeable bag body (41) and a vegetation base material (42) filled in the bag body (41). The bag body (41) and the reinforcement (3) are fixedly connected together by a reinforcing wall (6) so as to form a whole body by the reinforcing wall (6), the reinforcement (3) and the vegetation bag (4). The ecological greening wall has a simple and firm structure, and it is easy to be constructed.