The present invention relates to a cyclic peptide from a novel bone morphogenetic protein 2 (BMP2), a preparation method therefor and an application thereof. The cyclic peptide from the novel BMP2 is selected from one of the following cyclized polypeptides: 1. a cyclized polypeptide having the sequence of CKIPKASSVPTELSAISMLYLGPGGDWIVAC; and 2. a cyclized polypeptide of which the sequence has an 80% homology with the sequence defined in item 1. The present invention also relates to a preparation method for the cyclic peptide from the novel BMP2, and an application thereof in the preparation of the composite material for promoting the repair of large-sized bone defects.
