The Centre for Food Safety has banned the import of poultry meat and products, including poultry eggs, from Merced County in California.
The ban was imposed after US authorities announced an outbreak of low pathogenic H7N3 avian influenza in the county.
The centre has contacted American authorities and will monitor developments.
About 267,000 tonnes of chilled and frozen poultry meat and about 530 million poultry eggs were imported to Hong Kong from the US last year.
