Abstract: Seismic design has the characteristic of self-fulfillment. Seismic behavior of members depends on three aspects: capacity, ductility and plumpness of hysteretic curves. Method for seismic design to standard GB 50017-2017 is introduced. For system performance factors the required modifications incorporating effects of short period, MDOF, second order effect and damping are introduced. The control of ductility development mechanism and its control method are introduced. A new explanation is provided for the enlargement of seismic effect in the bottom stories, finally the design technique of second-order analysis used for seismic design is discussed.