By solution polymerization，isophorone diisocyanate， bisphenol-A and hydroxyethyl methacrylate，etc.were used as the raw materials，and 1，4-butanediol and trihydroxymethylpropane were used as the chain extenders and crosslinkers， an photo-active polyurethane-gel prepolymer（IBGBMA） which could realize the chemical bond combination with the light-curable resin matrix was synthesied， and its structure was characterized by Fourier transform infrared spectroscopy（FT-IR）.The Bis-GMA/TEGDMA （7∶3） resin matrix without IBGBMA was used as control group， and the matrixes added with 5%， 10%， 15% and 20% IBGBMA were used as experimental groups. The volume shrinkage rates of each group after curing were detected by the density bottle method， and the universal testing machine was used to detect the flexural strength（FS） and elastic modulus（EM）， the Vickers hardness tester was used to detect the Vickers hardness， and the FT-IR peak area method was used to detect the double bonds conversion rate.

The FT-IR results showed the characteristic absorption peaks of a photo-curable group （C=C） at 1 638 cm^－1 as well as the group （－NHCOO－） at 3 310 cm^－1， indicating that the active target product IBGBMA was synthesized，which can polymerize with the resin matrix during light curing. With the increase of IBGBMA addition amount， the volume shrinkage rates in each experimental group were decreased， and they were all lower than those in control group （P<0.05）.Compared with control group，the FS and EM in 20%IBGBMA experiment group were decreased（P<0.05），but there was no statistically differences in the other experimental groups（P>0.05）.The Vickers hardness in various experimental groups was increased （P<0.05）.The double bond conversion rates in various experimental groups were decreased with the increase of IBGBMA addition amount， and they were all lower than that in control group（P<0.05）.

The light-curable active polyurethane-gel prepolymer is successfully synthesized which reduces the volume shrinkage. And the volume shrinkage rate in 15%IBGBMA group is significantly reduced， the Vickers hardness is significantly increased， while the EM and FS are not affected， so the comprehensive properties are improved.