The invention discloses a loess abrupt slope mixed plantation greening treatment method. The method comprises steps of tableland top forest belt greening, slope top greening in a downward hanging manner, slope surface greening, and slope base greening in a downward climbing manner. In the step of slope surface greening, at least one of the punching plantation greening technology and slotting plantation greening technology is employed for greening a slope surface soil mass firm area, grid wire meshes are employed to fix the slope surface in a slope surface soil mass loosening area, and then the soil mass loosening area can be greened through a manner that seedlings at the slope base climb upward and grow along the wire mesh grids. According to the invention, an upward hanging greening mode, a downward climbing greening mode, the punching plantation greening technology and pressure belt greening technology are integrally utilized, and the greening treatment is carried out through layer and region division, so that the difficulty of loess abrupt slope mixed plantation greening treatment is reduced, and loess exposed slopes in the north are treated through ecological measures.