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The hafnium rod blanks were processed into 13.3 mm hafnium bars by hot rolling and hot rolling plus cold forging respectively, and then vacuum annealed at 740 ℃×1 h. The microstructure, tensile properties and fracture morphology of the hafnium bars prepared by these two methods were compared. The result shows that at the same processing rate，the room temperature and high temperature tensile strength and yield strength of the hot-rolled and cold-forged samples in the unannealed state are significantly higher than hot-rolled samples, but the plasticity is lower. The fracture dimples are large and shallow. The room temperature and high temperature tensile strength and yield strength of the hot-rolled and cold-forged samples are slightly higher than hot-rolled samples after vacuum annealing at 740 ℃, the yield ratio is significantly increased, the size and depth of fractured dimples are approach to the hot-rolled samples. Increasing the certain degree of cold working on the hafnium bar is benefit to obtain better tensile properties in the later stage.