The aim of this bachelor thesis is to build on the current studies and research the influence of the shear lag on diagrid and to compare it with the standard frame structure.The first part of the thesis deals with the theory of shear lag and its influence on the skeleton and tube structure. Subsequently, the structural system diagrid itself and its occurrence in the world is explained. The next chapter is subdivided into three subchapters, in which was described the modeling of diagrid in the Dlubal RFEM program, along with other structures. In this program we observed the effect of shear lag on the structure and compared the different densities of the diagonal grid on diagrid structure.We have come to a conclusion, that the diagrid overall as a structural system shows high efficiency in resisting the horizontal forces in high-rise buildings. The system works much better than the frame type of structure. Buildings with diagrid are the ideal structural system for high-rise buildings.