An air-bearing head slider supports an electromagnetic transducer opposed to a rotating recording medium or magnetic disk. The slider includes a slider body having a bottom surface opposed to the rotating magnetic disk, the bottom surface having an air-entry end and an air-delivery end with respect to an air flow generated between the slider body and the rotating recording medium. A central rail is provided on the surface of the slider body at the air-entry end. The central rail extends from the air-entry end and terminates on its way to the air-delivery end. Two side rails are provided on the surface of the slider body at the air-delivery side and extend from the air-delivery end and terminate on their way to the air-entry end. An air flow passage, extending from the air-entry end to the air-delivery end, includes air gaps defined between the central rail and the two side rails and an area on the bottom surface located downstream of the gaps, so that a negative pressure is generated in the downstream area due to the air flow passing through the gaps.