A new drug currently available for the treatment of IgA nephropathy is hydroxychloroquine, which reduces urinary protein and delays renal fibrosis. The 2021 KDGIO guidelines include hydroxychloroquine in the treatment of IgA nephropathy, and the drug still has the effect of lowering urinary protein in patients who are at high risk of progression despite the application of optimal supportive therapy. Hydroxychloroquine is an immunomodulatory drug with an unknown mechanism of action. It has been used in the past mainly for the treatment of lupus erythematosus and rheumatoid arthritis. It has now been found to have some therapeutic effect on IgA nephropathy. The more common side effect of hydroxychloroquine is skin irritation. In addition to this serious side effects such as retinopathy and bone marrow suppression may occur. It is contraindicated in allergy, pregnant/nursing women and children under 6 years of age. Hydroxychloroquine should be used under the supervision of a specialist in a regular hospital, and the fundus of the eye and the blood routine should be checked regularly to avoid serious adverse reactions.