The present invention relates to novel bacteriophages specific to Klebsiella pneumoniae strains, and compositions comprising the same. Particularly, polypeptides and their coding nucleic acid molecule of the novel bacteriophages are provided. The invention also relates to applications of the novel bacteriophages and the polypeptides in the detection/treatment/prevention of infection caused by Klebsiella pneumoniae strains. Development of immunogen and vaccine on the basis of the polypeptides are also provided.