In a magnetic head cleaning mechanism applicable to a magnetic tape apparatus employing a threading scheme, a cleaning brush is driven in a small space. The mechanism includes a threading arm to engage a leader block with a leader pin to draw the block engaged with the pin, a magnetic head to conduct data reading and writing operation on a magnetic tape, a rotatably supported brush link arm including a brush at a tip end thereof, and a cam gear disposed on the side of the magnetic head relative to a threader track. Ordinarily, the arm is on the side of the magnetic head relative to the threader track. When the leader block is moved to a position near the leader pin, the arm rotates with rotation of the cam gear to bring the brush into contact with the magnetic head on the threader track.