Abstract: A linear supramolecular polyurethane（HP1400-UPy）was obtained through interaction of —NCO end groups in prepolymer of polyurethane with —NH2 groups in ureidopyrimidone（UPy）, and a novel low polymer with three UPy units（T5000-UPy） was synthesized by polyetheramine T5000 with —NCO groups in UPy. Then, a series of supramolecular polyurethane network were obtained with different ratios of HP1400UPy and T5000-UPy, of which structure and properties were confirmed by FT-IR、1H-NMR spectroscopy、TGA、DMA and mechanical tests, etc. Results showed that the introduction of T5000-UPy had only a slight influence on the thermostability of supramolecular polyurethane network, but the tensile test showed greatly improvement of mechanical properties compared to the linear supramolecular polyurethane. According to dynamic mechanical thermal analysis with the increasing of the content of T5000-UPy, more and more networks in supramolecular polyurethane were formed, leading to the reducing of tan δ and the increaseing of Tg and storage modulus (E′).