To provide a pipe fastening device equipped with such use-friendliness and safeness as to easily fasten and fix, with high mechanical strength, first and second pipes crisscross arranged, without using a specified tool.

There is provided a pipe fastening device for fastening and fixing the first and second pipes 30, 40 crisscross arranged. In the pipe fastening device, steel wire is used which is made of a metallic material with an elastic certain length. Then, the pipe fastening device comprises a first flexure formed in a U shape in a middle portion of the steel wire, a pair of second flexures formed in an inverted-U shape, a pair of third flexures formed in a U shape are included a junction of the first and second flexure, and an aslope-formed steel wire assembly 10, and a steel plate assembly 20 in which its steel plate is made of a metallic material with an elastic certain length and a form bent at a certain angle is provided and then a groove in contact with the outer surface of the pipe is formed in one end of the assembly 20 and further a protrusion engaging with the third flexure is formed on right and left sides of the assembly 20.