To provide a hole processing tool which can prevent a lifetime from shortening caused by a flank wear, reduce the requisite frequency of regrinding of the cutting edge, and enable stable processing for a long period of time.

A body 11 of a hole processing tool is to be turned around the axis, where a cutting edge 14 is provided from the inner periphery side of the tool body 11 toward the periphery side, embodied as a drill to form a hole in a workpiece with the cutting edge 14 or a reamer to make internal surface processing of the processing hole in the workpiece, wherein a first flank 18 is formed in the rear in the tool rotating direction of the cutting edge 14 in its flank 16 while a second flank 19 is formed behind the first flank 18 in the tool rotating direction, and a step 20 one step retreated from the first flank 18 is formed between the first and second flanks 18 and 19.