A novel method of controlling the shape memory properties of shape memory polyurethane (SMPU) by addition of micro-phase separation promoters including 1-octadecanol (ODO) and liquid paraffin (LP) is reported. The results indicate that the strain recovery temperature and the strain modulus rate (Eg/Er) were increased significantly with addition of small amount of micro-phase separation promoters. Thus it can increase the shape memory fixity rate and other shape memory behaviors of SMPU.