Avian influenza viruses (AIVs) continue to circulate in live poultry markets (LPMs), posing potential risks for zoonotic exposure. To investigate the environmental circulation of AIVs and their potential epidemiological associations with human infection, we analyzed 7,956 environmental samples collected from poultry-associated settings in Henan Province, China, between 2020 and 2025. A total of 1,460 samples (18.35%) tested positive for AIVs. Multivariable logistic regression analysis showed that LPMs were significantly associated with higher odds of AIV detection (OR = 7.211, 95% CI: 5.039–10.319, P < 0.001), and the odds of AIV detection increased over the surveillance period (OR = 1.254, 95% CI: 1.210–1.301, P < 0.001). Multiple AIV subtypes were detected, and H9N2 remained the predominant subtype throughout the study period. Five human infections were identified, including H5N6 and H3N8 infections in 2022 and three H9N2 infections in 2025. Serological surveillance of occupationally exposed individuals identified H9N2-seropositive and H3N8-reactive samples, indicating exposure to avian influenza viruses or antigenically related viruses. Phylogenetic analyses revealed genetic similarities between human-derived viruses and environmental viruses detected in poultry-associated settings. Three H3N8 viruses, including one isolated from a human case, formed a distinct phylogenetic cluster, and their internal genes were closely related to co-circulating H9N2 viruses. These findings demonstrate sustained circulation of multiple AIV subtypes in poultry-associated environments and highlight the importance of integrated environmental and human surveillance for the early detection of viruses with zoonotic potential.