α, ω-Hydroxybutyl polymethylphenylsiloxane was prepared by the equilibrium polymerization of cyclomethylphenyltrisiloxane, which was synthesised from methylphenyldichlorosilane under ZnO catalyst. Polyurethane modified with polyorganosiloxane elastomer was prepared from polyorganosiloxane prepolymer and polyurethane prepolymer, which had terminated diisocyanate group. α, ω-trimethoxysilyl polyurethane modified with polyorganosiloxane hybride elastomer (CUMPS) was prepared by the reaction of polyurethane modified with polyorganosiloxane elastomer and aminopropyltrimethoxysilane. Their structures were confirmed by the measurement of FT-IR and NMR, and the thermal properties were studied from DSC and TGA. Glass transition temperature of CUMPS exhibited exothermic peak at -41.8 ℃, and residual weight was 29 31% at 800 ℃ in air. Adhesion characteristics, elongation and load for CUMPS, prepared from polymethylphenylsiloxane, were better than CUMPS that was prepared from polydimethylsiloxane and polydiphenylsiloxane.