Porcine enteric adenovirus serotypes 1-3, previously shown to be distinct antigenically, were purified by density gradient centrifugation, and the DNA was extracted. Fragments generated by digestion with restriction endonucleases BamHI, EcoRI, HindIII, and PaeR7 were separated by electrophoresis and compared with human adenovirus type 2 as a control. The results demonstrated that the three porcine viruses were closely related to each other, although distinguishable, and distinct by restriction endonuclease analysis from human, murine, canine, bovine, and fowl adenovirus.