A rotary table system having high axial and radial run-out accuracy, high resolution, and thin and medium- or large-sized system. The rotary table system includes a guide apparatus and a rotary table mounted on the guide apparatus. The guide apparatus includes a ring-shaped integrated rail having no discontinuity in the travel direction thereof, and a plurality of guide blocks assembled to the rail from the direction of their surfaces opposing the rail. The surface of the rail opposite to the surface thereof opposing the guide blocks and the underside of the rotary table are joined together. The rail has an L-shaped cross-sectional configuration formed from a vertical portion and a horizontal portion extending from the upper end of the vertical portion in the radial direction of the rotary table. A tape scale that is detected by a detecting mechanism is provided on the outer peripheral surface of the rail.