A novel cytopathogenic paramyxovirus was isolated from a lung sample from a piglet, using continuous porcine alveolar macrophage cells. Morphologic and genetic studies indicated that this porcine virus (pPIV5) belongs to the species Parainfluenza 5 in the family Paramyxoviridae. We attempted to determine the complete nucleotide sequence of the first Korean pPIV5 isolate, designated KNU-11. The full-length genome of KNU-11 was found to be 15,246 nucleotides in length and consist of seven nonoverlapping genes (3'-N-V/P-M-F-SH-HN-L-5') predicted to encode eight proteins. The overall degree of nucleotide sequence identity was 98.7 % between KNU-11 and PIV5 (formerly simian virus 5, SV5), a prototype paramyxovirus, and the putative proteins had 74.4 to 99.2 % amino acid identity to those of PIV5. Phylogenetic analysis further demonstrated that the novel pPIV5 isolate is a member of the genus Rubulavirus of the subfamily Paramyxovirinae. The present study describes the identification and genomic characterization of a pPIV5 isolate in South Korea.