Abstract: The structural characteristics of the metallic metallurgical composite pipe are described here in the paper. Also theoretically analyzed and studied are such aspects of the said pipe,including the corresponding internal pressure level and stress distribution in elastic state and elastoplastic state,and the relationship between the internal pressure and the wall thickness and strength of the inner and outer metal layers,based on which the calculation model for the wall thickness of the inner and outer metal layers of the composite pipe is set up. The research result is worth providing the theoretic basis and reference for the structure design of the bimetallic composite pipe.