Objective <p>Carbapenem-resistant <i>Klebsiella pneumoniae</i> (CRKP) has emerged as a critical global public health. To investigate the dynamic changes of drug resistance genes and virulence traits in carbapenem-resistant <i>Klebsiella pneumoniae</i> during colonization-infection transitions, supporting clinical prevention strategies.</p> Methods <p>A total of 18 cases each of CRKP colonization-to-infection and infection-to-colonization were enrolled from ICU patients. Genomic DNA from 72 isolates was used for PCR detection of resistance genes, virulence genes, and capsular serotype genes among the 72 isolates. KPC-positive isolates underwent Sanger sequencing for subtyping, and the string test was employed to assist in defining the hypervirulent phenotype.</p> Results <p>No significant differences were observed in clinical features between groups. All isolates carried <i>bla</i>_{<i>KPC−2</i>} without other resistance genes. The colonization-to-infection group showed higher virulence gene detection rates (50.00% vs. 27.78%), with 4 cases exhibiting increased virulence genes during infection. Conversely, 2 cases in the infection-to-colonization group showed reduced virulence genes. Capsular serotyping identified three isolates (4.17%) carrying hypervirulence-associated serotypes: a K1 strain from a blood sample (Case 8) showing virulence gene increase during infection, and two K57 strains (Case 34) lacking virulence genes. 11 hypervirulent CRKP (15.28%) were identified, with 9 from the colonization-to-infection group.</p> Conclusion <p>CRKP maintains stable resistance genes during colonization-infection transitions, but dynamic virulence changes indicate higher infection risks when colonization converts to infection. Enhanced monitoring of virulence and resistance is critical to control hv-CRKP spread in ICUs.</p>