The activities of different aluminium powder were studied by means of gasometric method. The results show that the activity of spherical nano-aluminium powder is 76.1%, and the activity of common flake aluminium powder is 43.0%. Particle sizes had significent effects on activity of aluminium powder. The shelf-life prediction of nano-aluminium was studied by accelerated test and Berthlot method. If the change values of nano-aluminium powder (10%,20% and 30%) as expiation standards, the shelf-lives of nano-aluminium powder are predicted (4.73a, 9.77a and 14.80a) at 25 ℃.