Abstract: In traditional aseismic analysis of structures, the influence of the rocking component is often overlooked, which may lead to an underestimation of the structural response. To evaluate the impact of the rocking component on the structural response, a 5-storey steel frame non-isolated model and an isolated model were investigated. The conversion base shearing force method is proposed. The rotational acceleration of rocking component is converted into a translational acceleration through the concept of the effective height. The principle of the base shearing force method is adopted to calculate the base shearing force of the structure under the rocking component alone. By comparing with the base shearing force measured by the shaking table test, it is shown that the conversion base shearing force method could better estimate the base shearing force of the structure under the rocking component. Further, based on the effective height conversion, the acceleration response spectra of the coupled rocking component (X+RY direction) and the sole translational component (X direction) are compared. It is found that the coupled rocking component would lead to an increase in the response spectra amplitude, especially in the short-period range. When conducting the assessment of structural seismic response, the effect of the rocking component should not be ignored.