Abstract: Renal fibrosis is a common pathological change from development to end-stage renal diseases in all progressive chronic kidney diseases. Renal fibrosis after kidney transplantation will severely affect the renal graft function. Macrophages are characterized with high heterogeneity and plasticity. During the process of kidney injury, macrophages are recruited, activated and polarized by local microenvironment, and participate in the process of renal tissue injury, repair and fibrosis through multiple mechanisms. Recent studies have shown that macrophages may transit into myofibroblasts and directly participate in the formation of renal fibrosis. This process is known as macrophage-myofibroblast transition. Nevertheless, the regulatory mechanism remains elusive. In this article, the role of macrophages in renal fibrosis, the characteristics of macrophage-myofibroblast transition and the possible regulatory mechanism were reviewed, aiming to provide reference for relevant research of renal fibrosis.