Abstract: Objective　To explore the molecular epidemiologic characteristics of New Delhi metal-β-lactamase (NDM) carbapenemase producing Klebsiella pneumoniae strains. Methods　From September 2013 and March 2016, the carbapenemresistant Klebsiella pneumoniae (CRKP) were collected from hospitalized children. The NDM carbapenem gene was identified by PCR and DNA sequencing. The NDM carbapenemase producing CRKP strains were typed using pulsed-field gel electrophoresis (PFGE) and BioNumerics software. The clinical characteristics of children with different strains were compared. Results　In 93 CRKP strains, a total of 42 strains of NDM carbapenemase producing CRKP were detected, including 23 NDM1 and 19 NDM-5 carbapenemase producing strains. The NDM carbapenemase producing CRKP strains were divided into 14 types (type-A~N). Type-A, type-M and type-N were the dominant types, accounting for 69% (29/42). The other 11 types were non-dominant types, accounting for 31% (13/42). Type A strains (24%, 10/42) all produced NDM-1 carbapenemase, and type M strains (17%, 7/42) mainly produced NDM-5 carbapenemase. Type N strains (29%, 12/42) all produced NDM-5 carbapenemase, and the other 11 strains (31%, 13/42) mainly produced NDM-1 carbapenemase. The dominant strains were prevalent in pediatric ICU, while non-dominant strains were distributed in all pediatric wards. Infection rate after 48 h since admission, proportion of  indwelling drainage tube and duration of ICU stay in patients infected with dominant types were higher than those in patients infected with non-dominant types, and the differences were statistically significant (P<0.05). There were no statistically significant differences in age, gender, antibiotic usage, prognosis between the two groups (P>0.05). Conclusions　The NDM carbapenemase producing CRKP isolated from hospitalized children mainly produced NDM-1 or NDM-5 carbapenemase. Type A, M and N strains were three dominant PFGE types, which spread in a small scale in pediatric ICU wards.