Ni-Al 2 O 3 catalysts are prepared via the co-precipitation method using various precipitants: urea, Na 2 CO 3 , NaOH, K 2 CO 3 , KOH and NH 4 OH. The effects of the precipitants on the physicochemical properties and catalytic activities of the Ni-Al 2 O 3 catalysts are investigated. The Ni50-urea catalyst displays the largest specific surface area and the highest pore volume. This catalyst also exhibits the highest Ni dispersion and the largest Ni surface area. Ni50-urea catalyst prepared with urea as precipitant and Ni50-K 2 CO 3 catalyst prepared with K 2 CO 3 as precipitant exhibit high pore volumes and good catalytic activities for methane steam reforming. The Ni50-urea catalyst exhibits the best physicochemical properties and shows good catalytic activity and a strong resistance to electrolyte contamination.