<p>Isothermal die forging is a critical forming process for producing high-performance, complex components. Traditional machining methods, often employed for manufacturing such components, have low material utilization, high costs, and long processing times. In this study, a tail wing was fabricated using isothermal die forging of an Al–Zn–Mg–Cu–Er–Zr alloy. The microstructure and mechanical behavior of different regions of the tail wing were analyzed, along with the metal flow behavior and microstructure evolution during the forming process. Furthermore, the plastic deformation behavior of the die forging tail wing was analyzed through finite element modeling. The deformation of the billet, combined with material flow accumulation at the tail wing’s surface, induced significant strain, promoting extensive continuous dynamic recrystallization (CDRX), which was identified as the primary deformation mechanism. The combined effects of mold friction and extrusion resulted in distinct flow lines in the components. The microstructure of the tail wing handle is primarily composed of deformed grains and numerous subgrain boundaries, which result from the relatively small deformation and insufficient energy for complete recrystallization. In contrast, the wing surface is predominantly composed of fine, equiaxed dynamically recrystallized grains. These findings offer valuable insights into the design of complex isothermal die forging dies and the optimization of part blank preparation.</p>