Abstract: Several kinds of poly［εcaprolactonecoγ(carbamic acid benzyl ester)εcaprolactone］ ［poly(CLcoCABCL)］ with pedant carbamic acid benzyl ester group were synthesized through ringopening polymerization (ROP) of εcaprolactone (CL) and γ(carbamic acid benzyl ester)εcaprolactone (CABCL) using Sn(Oct)2 as catalyst. Then a series of functionalized polyurethanes were prepared by polycondensation of poly(CLcoCABCL) with isophorone diisocyanat (IPDI) and 1,4butanediol (BDO). Their structures, molecular weight and molecular weight distribution were characterized by 1HNMR and GPC, respectively. Their crystallinity and mechanical properties were determined by XRD and mechanical testing machine.The results showed that the crystallinity of polyurethanes could be adjusted effectively and the toughness could be improved by introduction of the carbamic acid benzyl ester changing the content of the pendant group. Moreover, the ductibility of polyurethanes also was improved due pendant group.