To provide an inexpensive twist preventing method for a channel having high twist preventive effect which is capable of working the channel by a simple die.

In the twist preventing method for the channel, embosses are formed symmetric to the flexural center on a web surface of the channel having a U-shaped section and bent in the plane parallel to the web surface, and embosses are formed independently symmetric to the flexural center on a web surface of the channel having a U-shaped section and bent in the plane parallel to the web surface. By performing a relatively simple working of forming embosses on the web surface of the channel, the product is little twisted by the spring-back when detaching the product from the die after the pressing, the dimensional accuracy of the product is kept within a specification, and any inconvenience is not incurred in assembling components.