Diabetic nephropathy (DN) has been one of the major public health problems in China, and most patients eventually develop end-stage renal disease. In the context of research in "gut-kidney axis" in recent years, increasing evidence supports the dual influence of gut microbiota and kidney. This article elaborates the effects of gut microbiota of its metabolites (short-chain fatty acids axis, bile acids axis, and endotoxin axis) on insulin secretion and inflammatory response in different DN stages, and summarizes the different pathways of gut microbiota in early and middle/late DN stages in a view to providing new research orientations for multi-target therapy of DN.