Serum samples collected from feral and domestic swine (Sus scrofa) in Florida and feral swine in Georgia and Texas were assayed by plaque reduction for their virus neutralizing (VN) antibodies against the porcine transmissible gastroenteritis virus (TGE). None of 560 samples collected from feral swine contained VN antibodies for TGE virus, but experimentally infected feral swine seroconverted. None of 665 samples from domestic swine contained TGE-VN antibodies. These results indicate feral swine are not a significant reservoir for TGE virus in southern states, but are capable of becoming infected and developing VN antibodies against TGE.