The unconstrained reversible shape-memory effect (URSME), which appears as an elongation of pre-deformed sample during non-isothermal crystallization and the following contraction during heating in the stress-free conditions, was recently discovered in crosslinked semi-crystalline polymers. The preconditions for the appearance of URSME are deformation of molten sample, cooling under load below crystallization temperature and subsequent unconstrained partial melting of crystalline phase. The goal of present work was to test the binary and ternary crosslinked blends of high-density polyethylene with ethylene-1-octene copolymers with two degrees of branching for URSME. The thermal analysis revealed the considerable enthalpic effects of crystallization and melting of the blend components in wide temperature range, indicating the fundamental possibility of choosing the temperatures, at which partial melting of crystals can be achieved. The SM investigation was carried out by means of thermo-mechanical tests, which implied preliminary melting of one or two (in case of ternary blends) crystalline phases with lower melting point, while high-temperature crystalline phase was crystallized storing a part of programming deformation. Obtained results have shown the distinct manifestation of URSME resulting in about 10-15% of strain increment during crystallization. It is concluded that the most pronounced URSME is observed when the high-temperature crystalline phase is enough elastic and does not prevent the oriented growth of crystals with lower crystallization temperature. At the same time, blend component with higher crystallization/melting temperature has to possess enough high crystallinity and to be well coupled with other phase/-s in order to store a deformation, which is sufficient to cause exactly oriented crystallization of low-temperature blend component/-s. Undoubtedly, received results enables creating of a new class of actuators on the basis of polymer blends.