In April 2021，the first human case of infection by the H10N3 subtype avian influenza virus （AIV）was identified in Jiangsu，China. The genetic diversity and molecular characterizations of H10N3 subtype AIV from live?poultry markets in China were studied. This strategy could enable understanding of the evolutionary origin of human?infecting H10N3 AIV and assessment of its spillover risk from poultry to humans. From June to December 2021，real?time reverse transcription?quantitative polymerase chain reactions were undertaken to detect H10N3 subtype AIV in poultry markets and environments in Anhui， China. Six strains （AH01–AH06）of H10N3 subtype AIV were isolated and identified. The whole?genome sequences of these viruses were amplified by high?throughput sequencing，and their genetic characterizations were analyzed. One of the six H10N3 isolates was found in an environmental sample collected in November 2021，and the remaining five were from chicken?throat swabs collected in June，November，and December 2021. Strains isolated from the same live?poultry market exhibited genetic diversity and differences in reassortment patterns. Among the six H10N3 isolates，the eight gene segments of four isolates （AH01–AH04） had nucleotide homology >99.00%. The PA gene segment of A/chicken/Anhui/11?30?YHZGS024?O/2021（AH05），and the PA and MP gene segments of A/chicken/Anhui/06?26?YHZGS006?O/2021 AH06）shared low homology with those of the other four H10N3 isolates，with genetic identities <97.04%. Phylogenetic analyses showed that the HA and NA genes of the six H10N3 isolates and human H10N3 strain fell within the Eurasian lineage，and their internal genes were derived from the AIV of the H9N2 subtype. The eight segments of AH06 were placed in the same branch with the human?infecting H10N3 strain，while the PA gene of other isolates was grouped with human? infecting H3N8 and H9N2 AIVs： the MP gene was more closely related to human?infecting H9N2 AIVs. Molecular characterization showed that all six H10N3 AIV strains had mammalian adaptive mutations such as G228S， which could improve the binding ability to human?type receptors. In summary， we showed the：(i)persistent prevalence of diverse avian H10N3 viruses；(ii) novel human?infecting H10N3 reassortants might have been circulating in poultry in China，and highlighted that they possessed multiple mammalian adaptive mutations. This study provided a theoretical basis for assessment of the public?health risk of H10N3 AIV.