A 56-year-old woman with a history of diabetes mellitus presented with high fever but no abdominal pain. An abdominal computed tomography scan showed a large liver abscess. Hypervirulent, string test-positive, rmpA/ampA2-, and iutA-positive Klebsiella pneumoniae was rapidly identified from drainage fluid of the liver abscess using metagenomic next-generation sequencing (mNGS). After intravenous antibiotic therapy and drainage of the abscess, the patient's condition resolved. This case report highlights the value of mNGS in rapidly and accurately identifying a pathogenic microorganism, which helps reduce the incidence of antimicrobial resistance and enables the targeted use of antibiotics.