A magnetic head slider comprising: an air inflow end; an air bearing surface; and an air outflow end, the air bearing surface comprising: an inflow side rail face further formed towards the air inflow end than the center of the air bearing surface; an outflow side rail face formed further towards the air outflow end than the inflow side rail face, having a magnetic recording/reproduction element arranged thereon; a negative pressure groove face formed between the inflow side rail face and the outflow side rail face; and a groove face formed between the inflow side rail face and the negative pressure groove face, or between the inflow side rail face and the outflow side rail face; and comprising at least one step structure shallower than the groove face at the slider end in the width direction of the groove face.