In case of any prevalence in pigs，swine influenza virus（SIV）would pose a certain threat to pig industry and public health. It was found that，by epidemiological surveillance on SIV H1N1 subtype，classical swine H1N1（CS H1N1），Eurasian avian-like H1N1（EA H1N1），human-derived H1N1 and 2009 pandemic H1N1（pdm/09 H1N1）subtype influenza virus were prevalent in pigs in China，all of which constantly produced genetic recombination with each others. In addition to infection in dogs，minks and other animals，some H1N1 subtypes of SIVs might episodically infect human，posing their potential threat to public health. In animal model experiment，the pathogenicity and spread ability of different H1N1 subtypes were different in mice，chickens，pigs and ferrets，some of which showed lethality，so it would be important to study their biological characteristics to evaluate any potential risk to human. SIV might lead to low level of mortality in pigs，which was less concerned，but its prevalence and biological characteristics should be timely investigated，followed by relevant control measures to reduce any possible economic loss and to avoid any occurrence of viruses with pandemic potential，as the avian and mammalian influenza viruses could be recombined into influenza virus strains in pigs，which might cause human pandemics. In a word，the prevalence and biological characteristics of SIV H1N1 subtype were reviewed in the paper，with a view to providing a theoretical basis for its control strategies.