Abstract: A novel fluid pulsation attenuation elbow was studied by the bidirectional coupling method, and the effects of structural parameters on its fluid-solid interaction characteristics were discussed. The results show that the internal total pressure difference is 29.506 27 kPa in the original elbow, the internal flow field is very uneven, the maximum deformation is 20.689 μm, the maximum stress is 180.08 kPa, and the deformation mode is that the structure is elongated in both sides, concaved in the middle and shows a double oval, and the deformation leads to the flare-out effect on the elbow. When guide plates are designed according to the golden ratio, the number, the radius and the length are 2 200 mm and 40 mm respectively, the total pressure difference is 10.707 87 kPa, it decreases by 63.71% in comparison with the result of the original elbow, but the maximum deformation is 330.39mm, and the maximum stress is 1 569.10 kPa. When the number of guide plates is 3, and the thickness is 3 mm in the final optimized structure, the internal total pressure difference is 12.469 56 kPa, it decreases by 57.74% in comparison with the result of the original elbow, the maximum deformation is 20.898 mm, the maximum stress is 259.80 kPa, and the internal flow field is very even.