PURPOSE: To provide such process for production of welded channel steel products that enable to form weld zones where reinforcement of weld parts of beads are extremely less at the time of butt welding the two rolled angle steel products.

CONSTITUTION: The ends of the two L-shaped rolled angle steel products 1a, 1b are butted against each other and are welded at a welding current of 100 to 350 ampere and a welding speed of 100 to 800mm/min by a plasma welding method in the process for production of the welded channel steel products by welding of the L-shaped rolled angle steel products 1a, 1b.