The invention discloses a composite silane coupling agent ternary composite positive electrode material for a solid-state battery, and is characterized in that the composite positive electrode material comprises the following materials: a ternary material, a conductive agent, polyvinylidene fluoride, polyvinylidene oxide and a lithium salt with the mass ratio of (75-92):(1-10):(1-6):(1-12):(1-7).The invention also discloses a preparation method of the composite silane coupling agent ternary composite positive electrode material for the solid-state battery, and also discloses an application ofthe composite silane coupling agent ternary composite positive electrode material for the solid-state battery. The composite positive electrode material has the advantages that a silane coupling agent is used for treating a positive electrode paste composited with an organic electrolyte, the surface of the inorganic powders (the positive electrode material and the conductive agent) can be organized and makes better contact with the organic electrolyte, the performance of a composite pole piece is improved, and the playing rate of the capacity of the positive electrode material is improved; and the process is relatively simple to operate, low in production cost, and beneficial for mass scaling.