To provide a theoretical reference for reducing the shrinkage and cracking of concrete and promoting the development and application of the shrinkage-reducing polycarboxylate superplasticizer, a shrinkage-reducing polycarboxylate superplasticizer (SR-PCE) with dispersion and shrinkage reducing properties was synthesized via free radical polymerization with isopentenyl polyoxyethylene ether (IPEG), acrylic acid (AA), butyl acrylate (BA) and other monomers. The molecular structure of SR-PCE was characterized by gel permeation chromatography and Fourier transform infrared spectroscopy, and its shrinkage reduction mechanism was analyzed. The results show that the molecular structure of SR-PCE is a designed structure. The optimum shrinkage reducing performance of the synthesized PCE can be obtained at a molar ratio of IPEG:AA:BA of 1:5:4. The mechanism of SR-PCE with the optimum shrinkage reducing performance mainly is since SR-PCE can further reduce the surface tension of the solution rather than ordinary PCE, SR-PCE can reduce the evaporation rate of the pore solution of cement paste and improve the pore water retention.