In order to solve the problem of the stainless steel pipe falling off during the debugging process of the cross arm rotating clamping mechanism, the TRIZ theory is applied to the innovative design of the mechanism. Firstly, the problem description, causal analysis and function analysis are carried out, then the invention principle and separation principle of conflict resolution theory and the standard solution of substance-field analysis model are used to solve the design problem. After feasibility evaluation, the optimization schemes such as changing the clamping direction and increasing the shape of the clamping rubber bulge are obtained. The optimized cross arm rotating clamping mechanism is applied to the stainless steel tube automatic packaging production line, which solves the problem of the stainless steel tube falling off, and provides a reference for the design of similar clamping mechanism.