Linear natural rubber bearing（LNR） isolators with large diameter and low IRHD rubber are analysed with FEM program.The stresses of the upper cover steel plate

the bottom cover steel plate and the inner steel plate of the isolator are researched.Some factors are considered

such as the constraints at the top of isolator

shear modules of the inner rubber

the ratio between thickness of one inner rubber and thickness of one inner steel plate etc.The results show that the maximum value of Mises stresses of the inner steel plate and the maximum value of normal stresses in the radius direction of the inner steel plate

are about 4 and 2.5 times the vertical pressures respectively;the stresses of steel of isolator are affected by the constraints at the top of isolator

especially for the upper cover steel plate of isolator.There is no effect on the stresses of the inner steel plate of isolator while changing shear modules of the inner rubber of isolator. The change of ratio between the diameter of core and the diameter of isolator will affect the distribution of the stresses of inner steel plate near the core.The ratio between thickness of inner rubber and thickness of inner steel plate has considerable influence on Mises stresses and normal stresses（in radial and circumferential direction of isolator） of the inner steel plate

but slight influence on the vertical normal stresses of the inner steel plate.