To provide a method and an equipment array for fabricating a welded tube by which edge waves before joining the edges of an open tube are stably prevented without interfering with another device to be inserted into a tube.

In the method for fabricating the welded tube by which band steel 25 is made into the open tube 23 by forming it by gradually bending the width by a forming roll group 8 and welding is performed while butting both edge parts 23a, 23b of the open tube 23 with squeeze rolls 22, center waves are imparted to a material to be formed by pressing only the center part 25c in the width of the band with a center pushing roll 1 on the upstream side of the squeeze roll preferably on the inlet side of the forming roll group.