PURPOSE: To make voids in the joints of each rail small even when comparatively long beams are employed as beams for supporting rails, and to ensure errors transmitted to a gap sensor in an extent that the errors are allowed for floating guide.

CONSTITUTION: In a rail device for a paraelectric magnetic floating car that floats the car by means of a paraelectric electromagnet while making the car travel by means of a linear motor, beams 7 in the lateral direction, portion materials for supporting a rail, are installed onto beams 6a, 6b arranged in order in the track direction, and rails 9, 9 are mounted to both end portions of the beams 7. The rails 9 are shaped so as to be slightly shorter than the lengths of the beams 6a, 6b and voids are installed among front and rear rails 9 at the both sides of the joint portions of the beams, but auxiliary rails 20, 20 connected by means of beams 21a, 21b each other are disposed to the void portions on the same line as the front and rear rails 9, thus effectively attaining the desired target