The invention discloses a steep slope embankment light combined supporting structure and a construction method. The structure and method effectively solve the technical problems that construction is difficult, investment is large and the risk is high of the steep slope embankment slope cutting construction in the high-cold and high-altitude area. The structure comprises lower anchor rod grouting foundations and upper anchor rod grouting foundations, lower supporting tables and upper supporting tables, supporting uprights, breast boards, supporting mechanisms and embankment projects; the loweranchor rod grouting foundations and the upper anchor rod grouting foundations are arranged on steep slope foundations of the lower slope side and the upper slope side of an embankment at intervals andin a row mode; the lower supporting tables and the upper supporting tables are arranged on the tops of the lower anchor rod grouting foundations and the upper anchor rod grouting foundations respectively, and circular arc-shaped groove openings are reserved in the centers of the tops of the lower supporting tables; the lower ends of the supporting uprights are arc convex structures, and are arranged in the arc-shaped groove openings arranged on the tops of the lower supporting tables; the breast boards are arranged between every two adjacent supporting uprights in a lap joint mode; the two ends of each supporting mechanism is connected with the top of the corresponding supporting upright and the outer side of the corresponding upper supporting table; and the embankment projects are filledon the steep slopes of the inner sides of the supporting upright and the inner side of the breast boards in a layered mode.