Abstract: Streamwise corner structures are widely present in geometrically complex regions of aircraft, such as component junctions, engine blade roots, and inlet rectangular cavities, and the complex flows induced by them directly affect aerodynamic performance. When turbulence passes through streamwise corners, it is primarily characterized by Prandtl's secondary flow of the second kind, often accompanied by complex flow mechanisms including transition, separation, and curved-wall effects. Although these motions are weak compared to the streamwise velocity, they have significant and profound effects on turbulence statistics. With the continuous improvement in performance requirements for long-range wide-body aircraft and high-speed vehicles, research on key aerodynamic issues such as streamwise corner flows has become increasingly urgent. Based on this, this paper systematically summarized recent research progress in this field from theoretical, experimental, and computational perspectives. It focused on the formation and evolution mechanisms of secondary flow, the corner-induced transition process, and provided an in-depth analysis of experimental findings from typical configurations such as wing-body junctions, square ducts, and cascades. In terms of computational methods, this paper not only summarized the improvements of eddy-viscosity models based on quadratic constitutive relations, but also analyzed the Reynolds stress model (RSM) including the transitional RSM developed by the authors' team, highlighting their advantages and challenges in high-order simulations. Finally, it is pointed out that high-fidelity prediction under complex configurations remains a bottleneck. Future efforts should focus on the development of turbulence modeling based on machine learning, high-precision optical experimental measurements, and further research on corner transition and anisotropy mechanisms, aiming to provide support for refined aircraft design.