Updated project metadata. Infectious bursal disease virus (IBDV) enters the host cells via endocytic pathway to achieve viral replication in the cytoplasm. We performed liquid chromatography-tandem mass spectrometry coupled with isobaric tags for relative and absolute quantification (iTRAQ) labeling of differential abundant protein species of IBDV-infected cells using a subcellular fractionation strategy. We find that viral infection regulates the expression and/or subcellular localization of more than one thousand host proteins in either the nuclear or the cytoplasmic fraction at the early phase of infection. These data provide clues to further understanding the replication and pathogenesis of IBDV and virus-host interactions.