Objective　To explore the diagnosis and treatment of Dent disease I. Method　The clinical data of 4 children with Dent diseaseⅠand the direct sequencing results of Dent disease-related genes CLCN5, OCRL1 exons and nearby regulatory regions were retrospectively analyzed. Results　All the four children were male, the age at onset was 1.5~4 years and the age at diagnosis was 3~10 years. All of them had the clinical manifestations of proteinuria, among which 2 cases were accompanied by rickets symptoms. Gene detection showed that all of them had CLCN5 mutations, L263F, R104X, S244L and exon 9-13 deletion respectively. S244L is the most common mutation in patients with Dent disease I, and the rest are newly discovered mutation sites. Conclusion　Dent disease I is mainly manifested as low molecular weight proteinuria and hypercalciuria. Gene detection contributes to the early and clear diagnosis.