A polishing holder arm includes a polishing holder mounting/dismounting device having a base section supported by a base plate through a horizontally rotational shaft to permit the device to rotate and move upward from an approximately horizontal position and the other end section engaged with the polishing holder H. The holder H includes a coupling section whose rotation is restricted by the polishing holder arm and which is detachably coupled with the polishing holder mounting/dismounting device at a center. A polishing force applying device A moves between a position where it applies a downward spring urging force to the polishing holder arm and a position where it permits the polishing holder arm to rotate and move upward. With this arrangement, the optical fiber end surface polishing device causes the polishing holder H to be easily mounded and dismounted on and from the polishing holder arm, can adjust a polishing force double and permits the polishing holder arm to jump upward and rotate at least 90° from an approximately horizontal position.