PURPOSE: To produce a stress corrosion cracking resisting steel tube while obviating the necessity of complicated stages by introducing inert gas, etc., into a high strength steel tube in an austenite region and forming a decarburized soft steel layer on the internal surface of the tube at the time of applying heat treatment, such as normalizing, to the high strength steel tube.

CONSTITUTION: At the time of subjecting a high strength steel tube to heat treatment consisting of normalizing, normalizing and tempering, or hardening and tempering, an inert gas, such as Ar and N2, a nonoxidizing gas free from O2, or a low-O2 gas containing trace amounts (≤ about 5%) of O2 is introduced into the tube in an austenite region. By this method, the amount of O2 in the tube can be controlled and a decarburized soft steel layer can be formed on the internal surface of the pipe, by which stress corrosion cracking resistance can be improved.