采用ＷＡＸＤ、ＳＡＸＳ和Ｘ－射线平板照相法研究了不同聚合条件和拉伸倍数下的晶性３，４－聚异戊二烯的结构．结果发现，降低催化体系反应速度有利于产物结晶；不同的含氮类给电子试剂对聚合物的结晶结构影响较大．取向样品随着拉伸倍数的增加结晶度和长周期增大，微晶尺寸变小．ＳＡＸＳ的散射强度计算表明，该聚合物属多分散非均一粒子体系，微孔半径在３．５－１６．４ｎｍ间． The structure of crystalline 3,4-polyisoprene with different polymerization conditions and draw ratio was studied by WAXD, SAXS and X-ray plate. The results showed that reducing the reaction rate of the catalytic system is beneficial to the crystallization of the product; different nitrogen-containing electron donating agents have a great influence on the crystal structure of the polymer. As the draw ratio increases, the crystallinity and the long period of the oriented sample increase, and the crystallite size becomes smaller. Scattering intensity calculation of SAXS shows that the polymer belongs to polydisperse heterogeneous particle system with pore radius of 3.5-16.4nm.