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This work reports two preparation methods of Ni-Al₂O₃ composite to be used as a hydrogen separation membrane. The first method was powder impregnation while the second method was soaking-drying-firing or bulk impregnation. In the first method, the 10 wt pct Nickel (II) nitrate hexahydrate solution was mixed with Al₂O₃ powder. The mixed powders were dried at 100°C and uniaxially pressed into a disk shape at 7 MPa. The densification of composite membranes was accomplished by pressureless sintered at 900-1300°C. For the second preparation method, the Al₂O₃ disk support was prepared firstly by uniaxially pressing Al₂O₃ powder at 7 MPa and then sintered at 1000-1200°C for 2 h. After that, the Al₂O₃ support was soaked into 10 wt pct Ni solution, dried at 100°C and calcined at 900°C for 2 h. The soaking-drying-firing sequence was repeated ten times to finally obtain the Ni-Al₂O₃ membranes. After preparation process, the membranes fabricated from these two methods were reduced at 910°C for 2 h in hydrogen atmosphere. The effect of the preparation method on properties of membranes in terms of density, porosity, phase and microstructure are discussed.