Abstract: The flexural mechanical properties of bundled conductors in substations have great influence on the seismic responses of coupling electrical equipment. To obtain the flexural mechanical properties of bundled conductor as the bending stiffness of sub-conductors were concerned, a flexural mechanism model of bundled conductor based on chained beam-constraint-model（CBCM） was established in this paper. Based on CBCM, the influence of concentrated forces, the constraint effects of spacers and the geometric constraints were considered in the bundled conductor flexural mechanism model. Several typical examples and some parameters of bundled conductors were analyzed and the results of the bundled conductor model anastomosed the test results and finite element results well. What could be concluded is that the bundled conductor flexural mechanism model in this paper is valid and it could be used in the study of flexural mechanical properties of bundled conductors.