To improve the circularity of a foil assembly of a foil type fluid bearing.

This foil type fluid bearing B comprises an immovable retaining member 12 surrounding an outer periphery of a rotating journal with an annular clearance, and a foil assembly 13' fixed to an inner peripheral face of the immovable retaining member 12 and supporting the journal. The foil assembly 13' is formed by successively stacking a bump foil, a mid-foil and a top foil from a radial outer side toward an inner side. An inner peripheral face of the mid-foil is fitted to an outer peripheral face of a center pin 33 having a circular section, of a heat treatment holder 31 for solution treatment in a state that the bump foil and the mid-foil excluding the top foil, of the foil assembly 13' is welded to the immovable retaining member 12. Whereby the distortion of the inner peripheral face of the mid-foil is corrected to be close to a perfect circle, and the top foil welded to the immovable retaining member 12 is brought close to the perfect circle to be kept into contact with the inner peripheral face of the mid-foil, to improve the performance of the foil-type fluid bearing.