In the industry of semiconductor, LCD, PDP and sensitive equipments, the factory buildings have required more and more precise anti-vibration facilities, long span floor systems and short construction period for the realization of high techniques and initiative market share. Besides, the buildings require non-supporting construction method since the buildings should be designed with 8-9m floor height which generates problems of high-place form work and high-cost supports against buckling. Because of these requirements, The PC system is most appropriate for the construction of ultra precise industrial buildings. However, the PC members can be transported on the road by vehicles from PC factory to construction site within transportation regulation; length 16.7m, height 4m and weight 40tf including vehicle dimensions. This paper suggests the segmented PC floor frame systems, using classical Gerber-beam techniques for resolving the practical problems and restraints to the long span floors of anti-vibration industrial buildings. The vibration properties were analyzed with structural S/W program and the material amount and construction cost were examined for the confirming the efficiency.