To cut a row of pipes along a cutting line with high accuracy, and to increase the lifetime of a rotating saw blade by alleviating a load to the rotating saw blade.

In this pipe cutting method, a plurality of pipes P1 to P3 are cut by a rotating saw blade S along the cutting line direction crossing the row of pipes PW in which the pipes P1 to P3 are placed in parallel with one another at certain pitches on a plane. In addition, the pipes are cut by alternately repeating cutting feed operations C1 to C3 in which the rotating saw blade S is advanced and retracted toward the row of pipes PW to sequentially cut the pipes P1 to P3 and moving feed operations S1 to S3 for moving the rotating saw blade S in the cutting line direction. The moving feed operations are performed at certain pitches. Further, the finishing position of the cutting feed operation C1 is set as a position in which the merging portion of the pipe wall of the second pipe P2 is left and the whole cross section of the first pipe P1 is cut. The merging portion includes the maximum blade contact length of the rotating saw blade S with the pipes P.