The stability of catalytic activity and selectivity of Ni3Al for methanol decomposition were studied by life test at 633 K on the alkali-leached powder samples. The characterization of the samples was carried out by X-ray diffraction, inductively coupled plasma (ICP) analysis, SEM observation, and surface area measurement. The life test showed that the alkali-leached Ni3Al exhibits a very stable activity and a high selectivity for methanol decomposition. The surface characterization after reaction suggests that the high selectivity and stable activity may be attributed to the formation of tiny particles and porous structure which increased the surface area significantly during reaction. These results indicate a possibility of Ni3Al as a catalyst for hydrogen production reaction.