With complex development process and pathogenesis,age-related macular degeneration(ARMD)is a chronic and progressive macular degenerative disease,which is currently the leading cause of blindness in middle-aged and elderly people. Research showed that the choroidal thickness changed significantly in different stages and classifications of ARMD.Since choroid is a vascular structure capable of rapidly changing blood flow, the change in choroidal thickness may be mainly caused by the change in choroidal blood flow. In addition, the abnormal blood perfusion of choroid can further damage the function of the retinal pigment epithelium cells, resulting in hypoxia and ischemia of retinal pigment epithelium, and finally induced ARMD. At present, more and more people are aware of the importance of choroidal thickness changes in the diagnosis and treatment of ARMD. Therefore, this article will review the changes and pathogenesis of choroidal thickness and blood flow in the course or after treatment of ARMD, which may provide new predictor for ARMD onset, and provide new targets for the development of new treatments of ARMD.