A　spectral　element　method　was　used　to　analyze　dynamics　response　characteristics　of　the　complex　rigid　frame　structure.　The　local　dynamic　stiffness　matrices　of　straight　bar　and　Timoshenko　beam　could　be　established,　and　the　global　dynamic　stiffness　matrix　of　the　frame　structures　could　be　obtained.　Comparing　frame　harmonic　response　based　on　spectral　element　method　and　finite　element　method,　and　calculating　the　natural　frequencies　and　frequency　domain　results　under　impact　load　further,　it　shows　that　the　spectral　element　method　can　be　used　effectively　and　accurately　to　analyze　the　dynamic　response　characteristics　of　complex　frame　structures,　especially　for　the　high　frequency　responses,　and　the　precision　and　efficiency　are　high　compared　with　the　finite　element　method.