Abstract: Shape memory polymer (SMP) is a kind of smart materials that can maintain a temporary shape and recover its initial configuration under external stimuli. Its advantages of high shape fixation rate, high shape recovery rate, adjustable transition temperature, high deformation ability and light weight makes it suitable to design and fabricate deformable structures. However, its application is restricted by limited response modes and poor bearing capacity. These problems can be effectively solved by adding functional particles or enhanced fibers to the polymer matrix to obtain shape memory polymer composites (SMPC). This article first introduces the shape memory mechanism of SMP and gives its actuation methods. Then, fiber microbuckling behavior of unidirectional fiber reinforced SMPC is discussed. Finally, applications of deformable structures in aerospace are presented.