Abstract: OBJECTIVE To evaluate the spatiotemporal distribution and antimicrobial resistance profiles of hypermucoviscous Klebsiella pneumoniae (KP) in environmental wastewater in Pudong New Area, Shanghai. METHODS From Jan. 2024 to Dec. 2024, based on a prospective active surveillance study through a cross-sectional stratified sampling design, a total of 110 environmental wastewater sampling sites were selected across four geographical regions (urban, suburban, exurban and peri-urban) and three site types (residential communities, community hospitals and farmers' markets). Hypermucoviscous and non-hypermucoviscous KP isolates were identified, and genomic annotation and analysis were performed on hypermucoviscous third-generation cephalosporin-resistant KP (3GKP) isolates.RESULTS Among 1,320 wastewater samples, the isolation rates of KP and hypermucoviscous KP were 55.53% and 16.21%, respectively, with a hypermucoviscous KP ratio of 29.20%. No statistically significant difference was observed in the isolation rates of hypermucoviscous KP among the three wastewater settings (P=0.069), whereas significant regional differences were noted (P=0.002), with the lowest rate in urban areas and the highest in rural areas, showing an increasing trend from urban to rural regions. Among the 16 hypermucoviscous 3GKP strains, 11 were from residential communities, 4 from farmers' markets, and 1 from a community hospital. Sequence types (STs) were predominantly ST281 and ST1726, with bla_SHV and sul as the main resistance genes and IncFIB as the dominant plasmid type. Four ST1726/KL81 strains belonged to the same clone, originating from residential communities in suburban, peri-urban and rural areas, sharing identical resistance profiles and plasmid characteristics (bla_DHA-bla_SHV-qnrB-sul-IncFIB). In contrast, four ST281/KL64 strains were isolated from farmers' markets and residential communities in urban areas, exhibiting diverse resistance profiles and plasmid patterns. CONCLUSIONS This study establishes a baseline for the multidrug-resistant phenotype of hypermucoviscous 3GKP in the region. Genomic analysis reveals the diversity of locally prevalent sequence types and identifies the emergence of dominant clones in suburban and urban areas, thereby providing a foundation for future studies on KP ecological interactions and spatiotemporal resistance genomics.