ABSTRACT The coil is used for electrical connection and energy conversion in the electromagnetic pulse welding (EMPW) process, so its structure affects the welding effect. In this work, for the dual H-shaped (DH) coil, the influence of the symmetry coefficient on the Cu-Al sheets EMPW was studied through the simulation and experiment. When the voltage was 7 kV and the symmetry coefficient g was 0.75, 1, and 1.33, the V c-β trajectory curve contained by the simulation combined with the welding window curve (WWC) to analyze the dynamic process and welding effect. The relative impact speed was the fastest and the corresponding weld seam length was the longest when g was 1.33. The welding experiment results were consisted with the simulation results, it was beneficial to weld the Cu-Al sheets when g was 133. The symmetry coefficient could change the impact speed and angle to affect the welding effect. This work is of great significance for DH coil design.