Herein we report a novel homogeneous catalysis–liquid/solid separation catalytic system for highly effective recycling of homogeneous catalyst based on a phosphine-functionalized polyether guanidinium ionic liquid (P-PolyGIL) with a room temperature liquid/solid phase transition characteristic. This novel catalytic system has perfectly integrated the advantages of both the homogeneous and biphasic catalysis to realize the combination of the high activity, easy catalyst recycling and long service-life of the catalyst without a significant loss of the activity, selectivity and Rh for more than 30 cycles in the Rh-catalysed hydroformylation of higher olefins. The long service-life of the catalyst could be attributed to the efficient and practical strategy of the catalyst separation.