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Effects of disproportionation time and dehydrogenation pressure on the magnetic properties and anisotropy of HDDR magnetic powders were studied. The phase structures of the samples were identified by X-ray powder diffraction. The microstructure was investigated using scanning electron microscope. The magnetic properties of NdFeB were measured by AMT-4A magnetic measuring instrument. The results showed that the disproportionation time determines the content of the disproportionated phase and the residual parentNd₂Fe₁₄BH_1.04 phase in the material after the HD process. The residual parent Nd₂Fe₁₄BH_1.04 can inherit the texture information of the original Nd₂Fe₁₄B phase, which results in strong c-axis texture of new phase Nd₂Fe₁₄B. When the disproportionation time extends to 40 min, the anisotropy of the magnetic powder reaches the maximum, DOA=0.55. The dehydrogenation pressure mainly acts as the driving force for the crystal growth. The low pressure of 0.01 Mpa will cause over large driving force, which leads to the weak anisotropy of the generated new phase Nd₂Fe₁₄B. The magnetic powder has the optimum anisotropy when the dehydrogenation pressure is at 0.03 Mpa, DOA=0.53.