This research consists in determining the influence of the construction process has on the structural behavior (internal forces and maximum instantaneous deflections) of buildings with voided unidirectional slabs in site. To make analysis a 3D model of a building of eight floors plus basement was developed, using the finite element program ETABS. The beams and columns were modeled as elements type Frame and the slabs as elements type SHELL. To achieve this overall objective were performed 4 measurements, the first one in a conventional or linear way, the second one taking into account the three construction processes shoring - striking, partial striking and shored and 7 finally, using the temperature load. The results show that internal forces (maximum moments) found in model 2 are higher than the internal forces in model 1, with an increase of 13% corresponding to the shoring striking process, 18% for the partial striking process and finally to the shored process with an increase of 20%. Otherwise, as to the results of the instantaneous maximum deflections it was found that the deflections presented in model 2 are superior to model 1, showing increases in the shoring - striking process above 25%, in the partial striking process increases above 30% and in the shored process above 35%. In the case of the analysis of influence of temperatures in the increases in internal forces and maximum deflections instantaneous presented in the construction processes, it can be concluded that although their increases do not exceed 10% in the solicitation of internal forces as in deflections maximum instantaneous, is directly affected the transmission of loads in the moments that have installed metal struts, It is directly affected the transmission of loads in the moments that has metal struts installed, which suffer the phenomenon of shortening or lengthening according to the case, affecting their increased load transmission. In real life this situation happens daily when we see without any explanation the installed struts have run or moved from the place where they had installed before, being this case one of the possible causes of accidents during construction.