The study adopts the industrialized production of native efficient poly-Si wafers, the insulation of the 120s rapid heat treatment experiment under different temperatures has been carried out, explore annealing before and after the evolution of the poly-Si crystal defects such as grain boundary and dislocation and change of electrical properties. After 1200℃ annealing, dislocation density of ply-Si down to 710cm-2 by 1120cm-2, a drop to 36.61%. At the same time, the high Σ value (Σ27), a 1.62% reduction in grain boundary, Σ3 grain boundaries increased by 3.19%. After heat treatment, the minority carrier lifetime of sample can increase by up to 0.6μs. In addition, the size of grain would increase and the dislocation density reduced when grain orientation wasn’t changed during heat treatment. The results show that the improvement of the performance of poly-Si is related to the crystal structure of the silicon.