A multiplate friction clutch comprising: a clutch outer supported by a rotary shaft in a relatively rotatable manner about an axis, and holds a friction plate in a relatively displaceable manner in an axial direction of the rotary shaft; a clutch center supported by the rotary shaft in a relatively non-rotatable manner; a pressure plate assembled to the clutch center in a relatively rotatable manner about an axis and in a relatively displaceable manner in an axial direction, holding a clutch plate, which is brought into contact with the friction plate, in a relatively displaceable manner in the axial direction together with the clutch center, and having a boss portion which penetrates the clutch center; a clutch lifter plate joined to the boss portion and receiving a drive force in an axial direction at a time of disconnection between the friction plate and the clutch plate; a spring sandwiched between the clutch lifter plate and the clutch center, and capable of generating an elastic force in a direction that the friction plate and the clutch plate are pressed to each other; a position restricting portion which is provided on the clutch lifter plate, the position restricting portion being brought into contact with the boss portion from an outside in a radial direction of the clutch lifter plate so as to restrict a position of the clutch lifter plate with respect to the pressure plate; and a groove which extends in a peripheral direction of the clutch lifter plate and receives a tip end of the boss portion is formed on the clutch lifter plate, and the groove has: an outer wall surface which is brought into contact with the boss portion from an outside in the radial direction of the clutch lifter plate so as to function as the position restricting portion; a bottom surface which expands radially inward from the outer wall surface, and is brought into contact with a tip end surface of the boss portion; and an inner wall surface which expands while facing the outer wall surface, and faces the boss portion from an inner side in the radial direction of the clutch lifter plate, characterized in that the multiplate friction clutch further comprises a cam mechanism disposed between the pressure plate and the clutch center, and capable of generating a relative displacement in an axial direction between the pressure plate and the clutch center in response to a relative rotation about the axis between the pressure plate and the clutch center; and a space is formed between the inner wall surface and the boss portion. a clutch outer supported by a rotary shaft in a relatively rotatable manner about an axis, and holds a friction plate in a relatively displaceable manner in an axial direction of the rotary shaft; a clutch center supported by the rotary shaft in a relatively non-rotatable manner; a pressure plate assembled to the clutch center in a relatively rotatable manner about an axis and in a relatively displaceable manner in an axial direction, holding a clutch plate, which is brought into contact with the friction plate, in a relatively displaceable manner in the axial direction together with the clutch center, and having a boss portion which penetrates the clutch center; a clutch lifter plate joined to the boss portion and receiving a drive force in an axial direction at a time of disconnection between the friction plate and the clutch plate; a spring sandwiched between the clutch lifter plate and the clutch center, and capable of generating an elastic force in a direction that the friction plate and the clutch plate are pressed to each other; a position restricting portion which is provided on the clutch lifter plate, the position restricting portion being brought into contact with the boss portion from an outside in a radial direction of the clutch lifter plate so as to restrict a position of the clutch lifter plate with respect to the pressure plate; and a groove which extends in a peripheral direction of the clutch lifter plate and receives a tip end of the boss portion is formed on the clutch lifter plate, and the groove has: an outer wall surface which is brought into contact with the boss portion from an outside in the radial direction of the clutch lifter plate so as to function as the position restricting portion; a bottom surface which expands radially inward from the outer wall surface, and is brought into contact with a tip end surface of the boss portion; and an inner wall surface which expands while facing the outer wall surface, and faces the boss portion from an inner side in the radial direction of the clutch lifter plate, an outer wall surface which is brought into contact with the boss portion from an outside in the radial direction of the clutch lifter plate so as to function as the position restricting portion; a bottom surface which expands radially inward from the outer wall surface, and is brought into contact with a tip end surface of the boss portion; and an inner wall surface which expands while facing the outer wall surface, and faces the boss portion from an inner side in the radial direction of the clutch lifter plate, characterized in that the multiplate friction clutch further comprises a cam mechanism disposed between the pressure plate and the clutch center, and capable of generating a relative displacement in an axial direction between the pressure plate and the clutch center in response to a relative rotation about the axis between the pressure plate and the clutch center; and a space is formed between the inner wall surface and the boss portion.