A bacterial poly[(3-hydroxybutyrate)-co-(3-hydroxyvalerate)] biosynthesized by Pseudomonas sp. HJ-2 was found to be a shape memory polymer. Permanent shapes were set by annealing at room temperature the samples that had been pre-treated above 95 degrees C in specified shapes. The temporary shapes were set by stretching and holding the elongated samples. Thermal shrinkage began at 45 degrees C and stopped at 75 degrees C to recover to their permanent shapes. Apparently, the orientation induced the formation of hard segments that were responsible for setting the temporary shapes. The shape memory effect of this polymer was explained based on the DSc and XRD results at different phases.