Abstract: In order to improve the seismic performance of mega-frame structures, a new type of structural system, i.e. mega-frame structures with a vibration absorption substructure, was put forward. A typical mega frame structure and a mega-frame structure with a vibration absorption substructure were designed. Their elastic earthquake responses were analyzed and both results were compared. The influence of frequency ratio and damping on the damping effect was studied. The results show that the vibration absorption substructure has a significant damping effect which has an excellent robustness against the frequency ratio. The damping effect is increased significantly by increasing the isolation bearing damping coefficient ratios until they are greater than 0.4. This work will be helpful in theoretical research and give some assistance to practical engineering.