Dynamic characteristic parameters of two kinds of phenyl silicone rubber vibration isolator in aeroengine were studied experimentally. Firstly, the theoretical model of experimental measurement method was established, and the error of engineering approximate formula used in dynamic characteristic parameters calculation of isolator was analyzed. The accurate formulas and iterative algorithm were given. The dynamic stiffness and damping ratio of two isolators were measured by sweep vibration method at room temperature along three axes, and the dynamic stiffness and damping ratios of two isolators along x direction and at different ambient temperatures were also measured by same method. Experimental results show that at room temperature, the dynamic stiffness of two isolators along x direction is much larger than that along y and z direction. With the increase of ambient temperature, the dynamic stiffness of two isolators along x direction decreases gradually. The dynamic stiffness and damping ratio of the improved isolator with damping additive are greater than that of ordinary isolator.