PURPOSE: To cut a pipe in a correct length with its length at the normal temperature time as the reference, by sticking in advance an adhesive tape with a measuring scale to a pipe and marking a pipe cutting position with the use of the measuring scale thereof at the pipe line execution site.

CONSTITUTION: The marking of a cutting position is executed based on a measure by a measuring scale, on the plastic pipe 1 which sticks a plastic tape 3 with a measuring scale in the length direction. The adhesive tape 3 is then peeled off, the peeled tape 3 is wound in the peripheral direction at the marking position and a pipe is cut with this wound tape 3 as the cutting marked line. Consequently, the cutting marked line can be expressed straightly in the peripheral direction, the cutting can be performed smoothly and with aligned cutting face, and the pipe 1 can be cut with a correct length accuracy, because of the measuring scale being contracted at the same ratio as that of the plastic pipe 1 even in case of there being the thermal contraction of the pipe 1.