A disc drive has a loader, a traverse, a circuit board and a supporting frame. The loader has a first side wall, a second side wall and a third side wall that is perpendicular to the first side wall and the second side wall. The circuit board has a first side, a second side and a third side that is perpendicular to the first side and the second side. The supporting frame extends from the second side wall of the loader and has a supporting surface. The third side of the circuit board is shorter than the third side wall of the loader, and the second side of the circuit board is disposed on the supporting surface of the supporting frame.