Abstract: Protein splicing is post-translational process mediated by inteins. Inteins are internal protein sequences that self-excise and splice together the flanking sequences with a peptide bond. The discovery of inteins enhances theories of gene expression and post-translation, protein splicing technology can be applied in protein research and protein engineering. This review provides a survey of recent applications of protein splicing including protein labeling, protein segmental isotope-labeling, protein cyclization, protein chip, gene therapy and so on.