Abstract: A household clustering of human infection with avian influenza A (H7N9) virus involving 2 children occurred in Dongyang in February 2014. The detections of related alive poultry samples and environmental samples indicated that positive rate of H7N9 virus nucleic acid detected was 30%. To identify the infection source and the possibility of person-to-person transmission, epidemiological investigation and exposure matrix analysis were conducted. The results showed that case A had alive poultry exposure history and case B might be exposed to alive poultry too, but the possibility of person to person transmission could not be ruled out.