Proposed are a strain energy-based sensitivity analysis method and the corresponding evaluation index of cable-strut rupture for cable domes.Firstly,a sensitivity coefficient is defined as the ratio of the change amplitude of structural total strain energy in the vibration process after cable-strut rupture to that under the equilibrium before cable-strut rupture.Then,the defined coefficient is used as an overall index to evaluate the sensitivity of cablestrut rupture and is applied to the sensitivity analysis of cable-strut rupture for Levy cable dome.Finally,a comparison is made between the proposed method /index and the existing ones.The results show that Levy cable dome is most sensitive to the rupture of hoop cable and middle strut,and that the corresponding sensitivity coefficient reaches the maximum when the outer hoop cable is ruptured.Thus,the safety margin of hoop cable and middle strut should be both improved.The presented evaluation index is more applicable to flexible cable domes and is effective in representing the sensitive degree of structure to cable-strut rupture macroscopically.