Abstract: OBJECTIVE To explore the drug resistance and virulence characteristics of clinical isolates of Klebsiella pneumoniae from children with severe infection in Ningbo so as to provide experimental data for clinical treatment. METHODS Totally 98 clinical isolates of K. pneumoniae were collected from the children with severe infection who were treated in intensive care unit (ICU) of Ningbo Women & Children's Hospital from Jan 2020 to Jan 2022. The serotypes and virulence genes of the strains were detected by polymerase chain reaction (PCR), and extended spectrum β-lactamases (ESBLs) were screened by means of drug susceptibility disk method. RESULTS Among the serotypes of the 98 strains of K. pneumoniae, K1 accounted for 36.73%, K2 19.39%, K3 7.14%, K20 5.10%, K54 13.27%, K57 14.29%; 4 strains were not classified, accounting for 4.08%. Totally 96 strains were positive for wire drawing test, with the positive rate 97.96%. The K1 type strains carried with rmpA, wcaG, aerobactin, kfu and allS virulence genes. The K2, K3, K20, K54 and K57 types carried with rmpA and aerobactin genes; the K2 type also carried with wcaG, kfu and allS genes. Totally 46 strains of ESBLs-producing K. pneumoniae were detected among the 98 strains of K. pneumoniae. CONCLUSION The major serotypes of the clinical isolates of K. pneumoniae from the children with severe infection in Ningbo include K1, K2, K3, K20, K54 and K57 types; the strains carry with the virulence genes rmpA, wcaG, aerobactin, kfu and allS; the isolated rate of ESBLs-producing K. pneumoniae strains is high.