The master's thesis discusses the seismic analysis of a composite high-rise building. For the selected building, two concepts of load-resisting system are compared. In the first concept, horizontal loads are resisted with composite moment frames, whereas in the second concept horizontal forces are resisted through diagonal braces with buckling restrained members, which are also able to dissipate energy in the case of compression load. The introductory part of this master's thesis presents the constructional elements of the building, i.e. the composite slabs, the composite beams, the composite columns and the buckling restrained braces. Buckling restrained braces are relatively unknown to engineering practice, therefore their basic features and their expected seismic behaviour are also shortly summarized. In the central part of this thesis, the seismic analysis of the selected high-rise building is analysed considering two concepts of load-resisting system. Both concepts were designed in accordance with provision for seismic-resistant design (Eurocode 8) and other relevant parts of Eurocode standards. It is worth noting, however, that the Eurocode standards do not yet include specific rules for the design of buckling restrained braces. As a result, the design of this particular structural system was largely based on foreign standards and recommendations (NEHRP, 2015), published articles (Bosco in sod., 2012) and manufacturers' recommendations (Starseismic, 2017). The results of seismic analysis for the two concepts of the considered high-rise building were compared in terms of their flexibility (displacements), the base shear force and material consumption. Based on the results of the study it was observed that the displacements and story drifts are smaller in case of composite moment-resisting frame. Lighter construction is the one with buckling restrained braces.