Abstract: The coreless die hot spinning process of 6061 aluminum alloy was numerically simulated and analyzed by using ABAQUS software, and the non-uniform deformation along the tube billet thickness direction was analyzed systematically. The dislocation density, microstructure and grain sizes of the alloy after spinning were analyzed by electron backscatter diffraction (EBSD), and compared with the numerical simulation results. The results show that during the hot spinning process of 6061 aluminum alloy without core die, the outer layer of the tube billet has greater deformation and higher temperature than those of the middle and inner layer.The compressive stress decreases gradually along the thickness direction from the outer surface of the tube billet, which results in higher dislocation density and stronger dynamic recrystallization driving force than the middle and inner layers, thus increasing the recrystallization fraction of the outer grain of the tube billet and refining the outer grain. The degree of coincidence between the experimental results and the simulation results is good, and the reliability of the finite element model is verified.