IgA nephropathy can be diagnosed by urine examination, ultrasonography and renal biopsy pathology. 1. Urine examination: proteinuria quantification and typing are important for the judgment of IgA nephropathy condition and prognosis, because patients with IgA nephropathy will have episodic microscopic hematuria, asymptomatic microscopic hematuria with or without proteinuria. 2. ultrasonography: ultrasonography can be used as an auxiliary examination, which shows that both renal parenchyma echogenicity is increased and enhanced. 3. renal biopsy pathology: renal tissue biopsy is the gold standard for the diagnosis of lgA nephropathy, and the examination shows that the glomerular mesangial area or the capillary wall with lgA-based immunoglobulin in granular or clumped deposits. It is recommended that patients suspected of lgA nephropathy should go to the hospital in time for clear diagnosis and treatment under the guidance of doctors.