Abstract: In response to the issues of low efficiency and imbalanced duplex phase ratio in welded joints caused by complex thermal cycles in traditional arc welding of duplex stainless steel, this study proposes a novel high-efficiency magnetically controlled laser-MIG hybrid welding technique for 2507 super duplex stainless steel. A systematic study was conducted using Xiris cameras and a high-speed imaging system to investigate the plasma morphology and droplet transfer behavior under different excitation parameters, with the aim of elucidating the mechanism of the external excitation magnetic field in the laser-MIG hybrid welding process. The results show that the external magnetic field alters the forces acting on the plasma and droplet, thereby modifying the plasma morphology and droplet transfer mode. Within a certain range, the applied magnetic field can effectively regulate the plasma morphology, increase droplet transfer frequency, enhance droplet transfer stability, and improve weld formation quality. When the excitation current is 1.0 A and the excitation frequency is 75 Hz, the plasma exhibits a stable “bell-shaped” combustion profile, droplet transfer occurs in a stable jet mode, and the weld formation quality is optimal