IgA nephropathy is a glomerular disease in which IgA or IgA deposits predominate in the glomerular mesangial area, and is the most common primary glomerular disease. Nephrotic syndrome is a clinical manifestation that can be seen in a variety of renal diseases. The two are completely different, generally IgA nephropathy is defined on the basis of pathological manifestations, while nephrotic syndrome is defined on the basis of clinical manifestations. The connection between the two is as follows: IgA nephropathy can have the clinical manifestation of nephrotic syndrome; nephrotic syndrome can be seen in a variety of diseases including IgA nephropathy. IgA nephropathy manifests itself differently depending on the degree of the disease. IgA nephropathy may have simple microscopic hematuria, repeated episodes of microscopic hematuria with proteinuria, nephrotic syndrome, and acute renal failure in severe cases.The definitive diagnosis of IgA nephropathy requires a renal biopsy for pathologic examination. Typical manifestations of nephrotic syndrome are massive proteinuria, hypoproteinemia, edema, hyperlipidemia. The necessary conditions for the diagnosis of nephrotic syndrome are massive proteinuria (>3.5g/L) and hypoalbuminemia (serum albumin <30g/L). It is recommended that patients with IgA nephropathy or nephrotic syndrome should go to regular hospitals for further consultation, complete relevant examinations, and follow the doctor's instructions for symptomatic treatment.