The invention relates to a wide load boiler water cooled wall internal threaded pipe with fins with arc-shaped transition sections. The wide load boiler water cooled wall internal threaded pipe comprises a pipe body and the internal threaded fins spirally arranged on the inner wall face of the pipe body. The cross section of each internal threaded fin is in an isosceles trapezoid shape, and the connecting ace of the side face and the top face of each internal threaded fin and the pipe body is the arc-shaped section. The internal threaded fins can be used for designing and manufacturing a vertical pipe coil water cooled wall required by a wide load boiler, a pipe coil inlet of the water cooled wall needs no orifice ring, and the boiler mass flow velocity range is the medium-low mass flow velocity ranging from 300 kg/(m2.s) to 1300 kg/(m2.s). According to the wide load boiler water cooled wall internal threaded pipe, the heat transfer capacity, especially the heat transfer capacity under the medium-low mass flow velocity, of the internal threaded pipe can be enhanced, and the heat transfer character of a supercritical boiler under the low load is improved; and meanwhile, the flowing resistance of the boiler is reduced, wasted work of a water feed pump is reduced, and energy saving and consumption reduction of a power plant are promoted.