Abstract: A simplified model for evaluating stiffness or flexibility matrix used in free vibration analysis of space mega frames of super tall buildings has already be developed, which is a combination of the mega columns and beams with Winkler elastic-subgrade attained by the axial rigidity of the subsidiary columns within the mega frames. The whole mass of the structure is acted on its floors to determining the mass matrix. Thusly the proposed dynamic model was named space-member-storey model. Based on the model, a much more reasonable model is herein presented when resemble the stiffness/flexibility matrix, the mega columns of which are also simplified as members with elastic ground base obtained by the bending rigidity of the subsidiary frames within the mega frames. It is shown that the new model is rational and feasible. Consequently, a new method for the analysis of free vibration of space mega frames of super tall buildings is presented.