Pigs are susceptible to both human and avian influenza viruses and have been proposed to be intermediate hosts or "mixing vessels" for the generation of pandemic influenza viruses through reassortment or adaption to the mammalian host. In the study, for the first time, we summarize and report the coexistence of wholly human-like H3N2 viruses, double-reassortant H3N2 viruses and triple-reassortant H3N2 viruses in pigs in China, by analyzing the eight genes of swine influenza A (H3N2) viruses in China from 1970 to 2006. In 1970, the first wholly human-like H3N2 (Hong Kong/68-like) viruses were isolated from pigs in Taiwan, and then in the next years Victoria/75-like, Sydney/97-like, New York/99-like and Moscow/99-like swine H3N2 viruses were regularly isolated in China. In 1980s, two triple-reassortant viruses were isolated in pigs, which have been reported. Recently, the double-reassortant viruses containing genes from the human (HA and NA) and avian (PB2, PB1, PA, NP, M, and NS) lineages and the triple-reassortant viruses containing genes from the human (HA and NA), classical swine (NP) and avian (PB2, PB1, PA, M, and NS) lineages emerged in pigs in China. The coexistence of wholly human-like and reassortant viruses provides further evidence that pigs serve as intermediate hosts or "mixing vessels", and emphasizes the importance of reinforcing swine influenza virus surveillance in China.