A magnetic disk drive apparatus includes a housing member with first and second faces opposed to each other, at least part of each of the first and second faces being opened, a first cover member for covering the first face of the housing member, a second cover member for covering the second face of the housing member, a first HGA including a first magnetic head slider and a first suspension for supporting the first magnetic head slider, a second HGA including a second magnetic head slider and a second suspension for supporting the second magnetic head slider, a first support arm for supporting the first HGA, a second support arm for supporting the second HGA, a magnetic disk with both surfaces to which the first and second magnetic head sliders are opposed, respectively, and a motor for rotating the magnetic disk. The magnetic disk and the motor are attached to the housing member, the first support arm is attached to the first cover member, and the second support arm is attached to the second cover member.