PURPOSE: To solve instable running between a magnetic tape and a rotating post and generation of damages such as flaws of separation of the magnetic tape thereby to obtain remarkably high reliability by the magnetic tape running rotating post used in a magnetic recording/reproducing apparatus for recording/ reproducing the magnetic tape.

CONSTITUTION: In a magnetic reproducing apparatus, a magnetic tape running rotating posts 4, 4' rotating in touch with a magnetic tape 3 when the magnetic tape 3 runs are provided. The rotating posts 4, 4' are so constituted that a hard carbon film 2 or hard carbon film containing fluorine is arranged in a surface layer of a base material 1 of a high polymer resin. Accordingly, high reliability of the magnetic tape is maintained for a long time.