Abstract: A grille beam structure construction method for a semiconductor factory is configured to perform construction of grille beams without installation of a separate beam mounting the grille beams and to simplify a joint between the grille beams by using studs for mounting of the grille beams and by integrating grille beam members to each other by bolt-fastening. The method includes installing columns, installing studs between the columns at predetermined intervals longitudinally and transversally, mounting grille beams above the columns and the studs, wherein each of the grille beams includes an rectangular-frame-shaped edge beam and the edge beam has a plurality of fastening holes, and matching the fastening holes between the grille beams and inserting bolts into the fastening holes, thereby integrating the grille beam.