<p>Thin-walled 304 stainless steel tubes with annular inner ribs have high strength, high stiffness, and light-weighting characteristics, and have wide applications in the aviation, aerospace, and navigation fields. In this study, stainless steel thin-walled tubes with inner ribs were manufactured by hot power backward-spinning. The microstructural morphology, microhardness, and main texture evolution of typical regions of the tube were characterized and tested. The influence of different stress-loading conditions on the microstructure and mechanical properties of the tube was mainly studied. The numerical simulation for the hot spinning forming process of 304 stainless steel was carried out to analyze the material flow rules in the regions of inner rib and wall-thinning, as well as predict the height of inner ribs with different spinning parameters. The results showed that the thinning of the wall of the tube region is obvious, and the material in the inner rib region fills into the groove of the mandrel, and the loading paths of stress on the materials in these regions are different, and the wall-thinning region is subjected to axial and radial loads accuring plane strain, which leads to the transformation from the original equiaxial crystalline to elongated grains. The microstructure of the sample presented strong &lt; 111&gt;//AD texture for the reason of acutely axial load born from rotating tools during spinning. This study provides a reliable theoretical basis and technical reference for the optimization of the spinning forming process of stainless steel thin-walled tubes with annular inner ribs.</p> Graphical Abstract <p></p>