Abstract Taking the maximum double cantilever structure of rigid frame bridge in construction period as the research object, the structural dynamic response analysis under the combined action of extreme wind and wave is carried out, considering the influence of flow velocity. An analysis method of short-term pulsation effect of a structure is proposed considering the influence of various adverse factors under extreme wind and wave conditions, which provides a reference for structural safety assessment under extreme conditions; The dynamic response results of the maximum double cantilever structure of rigid frame bridge show that the wave-flow effect under extreme wind and wave conditions will increase the structural response during the construction period, resulting in adverse effects.