A kind of high trans-1,4-polyisoprene (TPI) was synthesized by coordinative polymerization of isoprene with supported titanium catalyst and triisobutylaluminium. The experimental results illustrated that the catalytic efficiency (CE) increases when the monomer concentration, polymerization temperature and time are increased. Under suitable conditions the CE can-exceed 2000 gTPI/gTi and the inherent viscocity of the TPI is about 4-6dl/g. The micro-structure of the synthesized TPI was characterized by IR and 13C-NMR spectra It was verifi-ed that the microstructure of the TPI is nearly all trans-1,4 chain unit(above 99%).Its melt-ing temperature is about 60℃ by DSC method.