Abstract: The effect of the number of different spaced voids but the same overall size on the evolution behavior of porous aluminum is studied by molecular dynamics simulation. The results show that on the state of same void shape size, with the increase of the number of the equality spaced voids, the time for the system to be stretched is shortened. And The time required in the evolution behavior (crack tip disorder-tip bluntness-lattice distortion-mother crack generation sub-crack) of the porous aluminum system is shortened during the process of loading,and the number of fluctuations is less and less.