Reinforced concrete bubble deck consists of recyclable plastic balls that are used to reduce the volume of concrete consumed and mainly in the middle of the slab, where the axial bending does not suffer a crisis with the reduction of a certain volume of concrete. Since the structure is composed of a combination of gravity and lateral loading system, the use of infill panel next to the bubble deck has a grate importance due the control of the seismic parameters. In most of the past researches, the behavior of sandwich infill panels has been examined on a small scale by researchers in a laboratory. However, the effect of gap in full-scale structures and the sensitivity measurement related to the effect of gaps in infill panels has been investigated less. Therefore, in continuation of the research of other researchers, in the present study, the effects of the infill panel gap have been investigated in addition to the combination behavior of bubble slab structures with 3D sandwich infill panel. In the process of non-linear solution, fiber plastic joints have been used in the column elements and non-linear layered shell elements in the infill panel and slab. After the numerical method was verified, various necessary numerical analyses performed and the obtained results have been measured. In this research, the seismic behavior of 72 models with the system of reinforced concrete bubble deck and sandwich infill panels has been investigated by push-over analysis method in the SAP2000 software. In these investigations, the effect of various factors including the ratio of span length to story height (L/H) 1.5, 2 and 2.5 and the number of stories 3, 6 and 9, as well as the effects of opening and gap in the infill panel, have been considered. The results show that the presence of the sandwich infill panels has a significant impact on the seismic parameters of the structure, especially the behavior and the ductility factor. In a general view, creating a gap in the connection bet