This article reported the diagnosis and treatment of a boy with Dent disease presenting with massive proteinuria.He was 3 years old and found to have massive proteinuria during routine physical examination without hypoalbuminemia, urine protein electrophoresis indicated mainly low molecular weight proteins, with hypercalciuria, and metabolic acidosis, no diabetes, no amino acid urine, and renal ultrasound showed no renal calcium deposition, He had no mental and physical developmental delay and no abnormal family history. Gene detection revealed one missense mutation in exon 15 of the OCRL1 gene, c.1477C > T (p.Arg493Trp). After the diagnosis was confirmed, restrictions in dietary intake of calcium, sodium, and oxalate was restricted and oral potassium citrate and hydrochlorothiazide was prescribed. During two months of follow-up, we observed a decrease in urinary calcium levels and normal renal function. This article aims to improve the understanding of this disease among physicians and provide reference for the diagnosis and treatment of this disease through typical case report and review of previous literatures.