IgA nephropathy (IgAN) is the most common primary glomerular disease in the world; it is associated with the intestinal microbiota, diet, genetics, etc., and is mainly diagnosed by kidney biopsy. Patients with IgAN may develop end-stage renal disease (ESRD) within decades of diagnosis, placing an enormous burden on patients and society. Therefore, early prediction and effective measures are needed to prevent disease progression. To date, a large number of studies have explored biomarkers of IgAN progression. In this paper, IgAN biomarkers are discussed to guide the early diagnosis, prevention, and treatment of this disease.