SRD5A3-CDG (MIM 612379) is an extremely rare congenital disease, with only 38 cases having been reported. Common manifestations are developmental delay, intellectual disability, ophthalmological abnormalities, cerebellar abnormalities, ataxia, and hypotonia. Here, we discuss a seven-year-old boy with SRD5A3-CDG (homozygous variant c.57G>A [p.Trp19Ter]), featuring the unprecedented finding of telangiectasia.