A composite design of multiple supporting structures is applied in a specific project,including double row piles, soil nailing wall, pile anchor support and small retaining wall on the top of piles. This system could solve the problem of slope support under two working conditions of temporary and permanent in limited space. The monitoring results show that the displacement control of the support structure is well, and the prestress loss of the prestressed anchor cable in the gravel soil layer is small in the short term.