This paper presents analysis of seismic shear design of twenty-story RC building designed in accordance with EN 1998-1. For this analysis, uncoupled ductile wall system is selected as structural system of building. Preliminary seismic analysis of structureis carried out using modal response spectrum analysis. The nonlinear time-history analysis is performed on the spatial model of the structure where the structure is exposed to seven real earthquake records selected in accordance with the rules defined in EN 1998-1. The subject of performed nonlinear time-history analysis is seismic shear design of DCH ductile walls in accordance with EN 1998-1. The analysis of determining design shear forces using magnification factor and analyses of diagonal compression and diagonal tension failure of the web due to shear for DCH ductile walls are performed. Based on the derived results, corrections for the magnification factor and for shear resistance of ductile walls are proposed. The analysis leads to conclusions regarding the design procedure for "large" ductile walls (L=6.0m), walls that accept the dominant part of seismic force, in relation to the "small" walls (L=3.0m), walls in which minimum reinforcement is relevant.