Abstract: In order to establish an accurate dynamic model of butted cylindrical shell structures and to solve the problem of lack of information of rotational degrees of freedom in the experimental model of butted cylindrical shell structures， the frequency response function based sub-structuring synthesis method is proposed. The equivalent multi-point connection method is used to approximately estimate the information of rotational degrees of freedom. Then the results are compared with the frequency response function results of the finite element method， verifying the accuracy of the method for cylindrical shell structure. At the same time， according to the different ways of obtaining the frequency response function of the substructure and the degree of freedom of the interface， the frequency response function based sub-structuring synthesis method is used for the hybrid modeling under various working conditions. Combined with the vibration characteristics of the butted cylindrical shell structure， the hybrid modeling results under different working conditions are compared and studied. Results show that the hybrid modeling accuracy of the butted cylindrical shell structure can be effectively improved by considering the information of rotational degrees of freedom of interface.