Congenital myotonic dystrophy is a severe and early-onset form of myotonic dystrophy (DM) with a prevalence of 2.5-5.5/100,000 live births. Expansion of the trinucleotide CTG repeat in the 3´ untranslated region of the DM gene, which is located at a chromosome 19q13.3 is a common mutation in DM. Clinical features are generalized hypotonia (floppy infant), respiratory and feeding difficulty, and the neonatal mortality rate is approximately 40%. We experienced a case of recurrent congenital myotonic dystrophy, and report with a review of related literatures. Women with recurrent neonatal hypotonia or ultrasonographic evidence of hypotonia, including positional abnormalities of the extremities and idiopathic polyhydramnios, should be offered testing for the genetic studies for myotonic mutation, such as PCR (Polymerase chain reaction) analysis and Southern blot analysis.