In order to explore the influences of shielding layer material, shielding layer thickness and via spacing on System in Package (SiP) on Electric field Shielding Effectiveness (SE) in conformal shielding structure, and to reduce simulation time cost, Taguchi method is introduced in this paper. Several typical frequency points were selected from 1 KHz to 20 GHz broadband, and the simulation model was established with the microstrip line structure as the radiation source and the conformal structure as the shielding layer. Build model and simulate based on orthogonal table design. Use the Taguchi analysis function that comes with the software to analyze the results obtained by the simulation, and obtain the weight of different factors that affect the SE. According to the results of Taguchi analysis, the structural factors of the shield layer are optimized and modeled. Compare the simulation results with the software prediction results, the two are highly consistent.