Recently, the hemizygous variation of SSR4 gene has been reported to be associated with congenital disorder of glycosylation type Iy. To date, only 13 patients have been diagnosed with SSR4-CDG in the worldwide, but it has not been reported in the Chinese population. […] We reported the first case of SSR4-CDG caused by SSR4 variant in Chinese population, expanded the clinical and mutation spectra of the disorder, clarified the genetic etiology of the patient, and offered support for the prenatal diagnosis of the index family.