In order to explore the underwater anti-explosion protection effect of different corrugated steel-concrete composite structures， the finite element-smoothed particle hydrodynamics （FEM-SPH） coupling algorithm was used to establish an underwater multi-media coupling explosion model. Different corrugated steel-concrete slab composite structure protection schemes were designed to explore the underwater wave cutting and energy absorption effects of different composite structure protection layers， including 3， 6， 9， 12 mm thick corrugated steel composite structure， 30°， 45°， 60°， 75° corrugated steel composite structure and 10， 30， 50， 70 mm wave height corrugated steel composite structure. The energy consumption sharing rate was proposed to evaluate the protection effect of the composite structure. The results show that simulation results of the front and back explosion surfaces of the concrete slab are in good agreement with experimental results， which verifies the simulation process of underwater contact explosion. Under different composite structure protection schemes， the peak pressure of the composite structure with 12 mm thick corrugated steel， the composite structure with 75° corrugated steel and the composite structure with 70 mm wave height is 63.2%， 60% and 57.9% lower than that of the unprotected scheme， respectively. The maximum protection rates are 63.2%， 60.0% and 57.9%， respectively， and the energy consumption sharing rates are 69.48%， 66.26% and 63.51%， respectively. The energy absorption effect and protection effect of the optimal composite structure with 12 mm thickness， 75° angleand 70 mm wave height are significantly better than those of the composite structure under the influence of single factor. The research results can provide a theoretical basis for the application of different corrugated steel-concrete composite structures in the field of underwater anti-explosion protection.