Abstract: The aerodynamics of bat flight, as a research hotspot, has been widely studied in the last two decades. The active flow control mechanism of dynamic deformation of bat-wings attracted great attention due to unknown unsteady aerodynamic mechanisms, which are different from those of birds and insects. According to the development of measurement tools, the studies of bat flight can be divided into three historical stages. In the first and second stage, the purpose of the studies is to select the "static" data. In the third stage, i.e., the present stage, the purpose is to measure the dynamic deformation of the wing and flow structure. Furthermore, we introduce the characteristics of bat wings, the kinematics of flapping, and the deforming wing, as well as the four typical models of morphing wing (twisting, cambering, bending and area-changing). The mechanisms of aerodynamic forces generation and wing morphing strategy are discussed preliminarily. In addition, the difficulties and challenges in the study of the aerodynamics in bat flight have been presented. Our next decade work may focus on solving these difficulties and challenges.