The backward extrusion experiment of bushing with tin bronze was conducted by induction heating up to 620-720 ℃, the microstucture of sample after extrusion was observed by optical microscope (OM), and the test of EBSD was conducted. The results show that with the temperature rising from 620 ℃ to 720 ℃, the recrystallization grain size is increased from 9 μm to 15 μm, and the ratio of grain length to diameter increases from 1.66 to 1.78. Thus, the isometric trend decreases and the grains are irregular. The study of misorientation and CLS grain boundary shows that with the increasing of temperature, the twin crystals increase gradually and mainly distribute inside the recrystallization grain. And the hot extrusion process is a plastic deformation process occuring due to the mixing mechanism that the dynamic recrystallization is dominant and the twin crystal is coordinated. However, the grain boundary distribution is given priority to large angle grain boundaries (> 15°), and a single pick characteristic displays. Thus, the peak appears at grain boundary angle of 60° with Σ3 grain boundary mainly. With the recrystallization, Σ CSL grain boundary is interconvert into each other, and Σ3 grain boundary is positively related to recrystallization fraction.