The stiffener effectively improves the strength of cold-formed members due to the enhancement of the elastic buckling moment of element plates in the cross-section. As for the symmetrically flexural member, channel, and Z- cross-sections with several V-shape stiffeners on the web have been studied to produce Lysaght’s Supa Cee and Zee. Channel sections with a V-shape stiffener on the web subjected to minor asymmetrical axis bending when the web is in compression have been studied recently. In the present paper, another type of stiffener, i.e., U-shape, was investigated. The critical moment and ultimate strength of 81 models of channel sections with and without stiffeners were computed using the software THIN-WALL-2 and the analytical expression of AISI S100. It was concluded that the U-shape stiffener installed on the web is effective for both buckling moment and ultimate strength. For the U-shape to be efficient, its width should not be greater than 0.4 times the web width, and the ratio between the depth of the stiffener and the flange width should be in the range of 0.1 and 0.4.