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Hypervirulent carbapenem-resistant Klebsiella pneumoniae (hv-CRKP) has been widely reported and poses a global threat. However, the comprehensive genetic structure of ST11-KL64 hv-CRKP and the possible evolutionary mechanisms from a genetic structure perspective of this high-risk clone remain unclear. Here, a bla KPC-2 - bla NDM-1 -positive ST11-KL64 hv-CRKP isolate was obtained from a human bloodstream infection (BSI). Whole-genome sequencing and bioinformatics analyses revealed that it contained a fusion plasmid, pKPTCM2–1. pKPTCM2–1 is a conjugative plasmid composed of an oriT -positive pLVPK-like virulence plasmid and a type IV secretion system-produced bla NDM-1 -bearing IncX3 plasmid mediated by IS 26 -based co-integration. This progress generated 8-bp target site duplications (TGAAAACC) on both sides. The fusion plasmid possessed self-transferability and could be transferred to bla KPC-2 -harboring ST11-KL64 CRKP to form the ST11-KL64 hv-CRKP clone. The pLVPK-like-positive ST11-KL64 strain exhibited virulence levels similar to those of the typical hypervirulent K. pneumoniae NTUH-2044. The mutation, Tet(A) (A276S), which was believed to lead to tigecycline resistance was observed. Overall, this high-risk clone has emerged as a tremendous threat in fatal BSIs and thus, targeted surveillance is an urgent need to contain the hv-CRKP clones. • One bla KPC-2 - bla NDM-1 -positive ST11-KL64 hv-CRKP in human bloodstream infection. • oriT -positive pLVPK-like virulence plasmid and bla NDM-1 -bearing IncX3 plasmid fusion. • One mutation of Tet(A) (A276S) maybe lead to tigecycline resistance. [ABSTRACT FROM AUTHOR]