The variable and strong random vibration caused by natural disasters such as earthquakes can cause great damage to the large-span concrete-filled steel tube column structures, resulting in life periodic attenuation of the whole structure of related buildings. This paper proposes a seismic performance testing method for large-span concrete-filled steel tube columns under random vibrations. Under the environment of variable and strong random vibrations, a test model was established; then, the vibration signal was separated from the noise by using the signal covariance matrix. The vibration signal was then processed by calculating the intensity, posterior density, and weight coefficient, and then the single life attenuation parameter was obtained. Afterwards, the particle swarm optimization (PSO) algorithm was introduced to solve the life attenuation suppression cycle of long-span concrete-filled steel tubular columns to judge their seismic resistance. The experimental results show that the judgement method for life attenuation suppression cycle of long-span concrete-filled steel tubular column structures can be used in the seismic test of relevant building structures under variable and strong random vibrations.