PURPOSE: To solve the problem with a full disc type brake friction plate that its friction surface is so close that powder formed by abrasion is likely to remain inside a frictional area, causing torque vibration and accelerating abrasion.

CONSTITUTION: A groove 2 is provided in the friction surface 1 of a friction plate in such a manner as to cross the surface. The groove 2 has its end portions open to the inner and outer peripheral surfaces of the friction plate. Powder formed by abrasion tends to move circumferentially on the friction surface and is therefore trapped in the groove 2 during a move and is moved within the groove by centrifugal forces and microvibration during braking and then released to the outside. Therefore, the possibility of stick-slip that could cause torque vibration is reduced and the possibility of the powder attacking the friction surface and thus accelerating abrasion is eliminated.