PURPOSE: To provide the inexpensive method capable of smoothly bending a pipe and protecting the bent part without flattering or crushing the pipe by using a spacer having an insertion part formed in a row of spherical bodies.

CONSTITUTION: When a pipe 3 is bent while the spacer for bending the pipe is inserted into the pipe 3 such as a copper pipe as it is, it can be bent easily and flexibly into shape such as a desired bend or elbow, because the insertion part 1 is constituted of a row of tied spherical bodies 11. On the other hand, since many tied spherical bodies 11 having a diameter nearly the same as the inside diameter of the pipe 3 are arranged in the pipe 3, crushing of the pipe diameter is prevented surely from the inner part. Since the space for bending the pipe has a construction light in weight, excellent in workability, low in cost when it is made of synthetic resin, etc., the spacer can be left inserted into the pipe as it is under construction. When this spacer is left inserted into the pipe as it is, the insertion part 1 serves as a protector to prevent the pipe 3 from being flattened, crushed, etc.