provided is a phb block copolymer having orientation - induced rubber - elasticity and temperature - sensitive shape memory effects , comprising a plurality of 3 - hydroxybutyrate blocks as a repeating unit and a plurality of 3 - hydroxyvalerate blocks as a repeating unit , and optionally a hydroxy acid repeating group containing 6 or more carbon atoms . the pha block copolymer exhibits orientation - induced rubber - elasticity and shape memory effects with a fast shape - recovery rate , and therefore such characteristics in conjunction with physical properties such as biodegradability and biocompatibility unique to pha enable application thereof to a variety of uses .