Abstract: Myopia is a process of ocular wall remodeling along with axial elongation after emmetropia decompensation, but the causal relationship among the changes taking place in ocular fundus structures during this process is not clear. The choroid, which lies between the retina and the sclera, plays an important role in the transmission of information related to myopia. The role of choroid in myopia is a hot research topic at present. Findings from animal experiments showed that form deprivation-induced changes in choroidal thickness may be related to the vascular perfusion, but the triggering mechanism of choroidal perfusion changes during the process of myopia still needs to to be further explored. Bruch’s membrane is an elastic membrane located in the front of the choroid with good contractile properties. In the process of myopia, regional changes of the synthesis or biomechanics of Bruch’s membrane may have formed the earliest structural basis of changes in choroidal thickness and blood flow. Taking choroidal thickness as a starting point, this paper focuses on the role and mechanism of Bruch’s membrane in the occurrence and development of myopia, which may further deepen our understanding of the mechanism of changes in choroidal thickness, and provide a theoretical basis for the development of new therapeutic targets for myopia.