Density functional theory has been employed to investigate the structure and stability of C@Al12Hn (1≤n≤7) clusters. Hydrogenated C@Al12 clusters exhibit pronounced stability for even numbers of H atoms. Large HOMO-LUMO gaps，large binding energy and increased ionization potentials imply that these clusters should be physically and chemically stable. The analysis of the charge density of the HOMO plot illustrates that a pair of hydrogen atoms prefer to occupy opposing on-top sites for clusters with an even n number. Studies of deformation charge density plots demonstrate that the bonding characteristic between the H atoms and the C@Al12 moiety is mainly covalent. The total magnetic moment is 1μB for C@Al12Hn with an odd number for n.