<p indent="0mm">First, this paper tries to review, summarize, and analyze the current status and problems of the aerodynamic mechanism research on the independent and coupling effects among the four factors that would affect the aerodynamic characteristics of bird wings—objectively and comprehensively. Second, based on the analysis and study of the current research results, according to the progress and limitations of calculation and experimental means, the paper puts forward the problems, strategies, and methods that need further study. The four main factors considered in this paper include the static geometric shape of the bird’s wing, four kinematic modes, the dynamic chord- and span-wise flexible deformation of the wing, and three kinds of small-scale flow-control structures that have recently attracted more attention. In this paper, in full consideration of wing static geometry appearance, kinematic modes, and dynamic, flexible deformation, by the analysis of the forces and vortex on a bird’s wing, the strategies and methods to further clarify the individual aerodynamic mechanism and function of the three small-scale flow-control structures are proposed. Furthermore, under the condition of mutual coupling among the four factors, the strategies and methods to obtain the aerodynamic mechanism of a real bird wing are also put forward. The viewpoints, methods, and conclusions of this paper have guiding and reference value for improving a bionic aircraft.