The present invention relates to a journal foil air bearing for supporting a load applied in the radial direction of a rotary shaft which rotates about the central line, the journal foil air bearing comprising: a top foil which is arranged to face the outer circumferential surface of the rotary shaft and to surround the rotary shaft; a bump foil which is a member that can be elastically deformed and is arranged to surround the top foil; a base foil which is arranged to surround the bump foil; a support portion which is provided at one end portion of the top foil and is provided to be supported by at least one of both end portions of the base foil and one end portion of the bump foil; and a coupling means which couples one end portion of the top foil, one end portion of the bump foil, and both end portions of the base foil to one another. According to the present invention, the top foil may not sag during use and may not shake up and down due to vibrations generated during use, and thus, effects of not generating an unstable rotation movement of the rotary shaft and preventing the top foil from being worn or deformed are obtained.