This paper obtains the lowest-energy geometric structures and the electronic and magnetic properties of small CuNiN clusters by using all-electron density functional theory.The calculated results reveal that the Cu atom prefers to occupy the apical site when N≤9 and for the clusters with N=10,the Cu atom starts to encapsulate in the cage.The CuNi7 and CuNi9 are magic clusters.The magnetism correlates closely with the symmetry of the clusters.For these clusters,the charge tends to transfer from the nickel atoms to the copper atoms.It finds that the doping of Cu atom decreases the stability of pure NiN clusters.