Possible geometrical structures and relative stabilities of (Ca3N2)n(n=1—4) clusters are studied by using the hybrid density functional theory (B3LYP) with 6-31G* basis sets. For the most stable isomers of (Ca3N2)n(n=1—4) clusters，the electronic structures，vibrational properties，bond properties，relative stabilities are analyzed. The following tendencies are revealed by the calculated results: the coordination number of N are usually 3—5. The bond lengths are about 0.231—0.251nm for Ca—N and 0.295—0.358nm for Ca—Ca. The population analysis suggests the average natural charges of N atoms are about -1.553e—-2.241e and those of Ca atoms about 1.035e—1.445e，the bonds between Ca and N are strongly ionic. The dynamic stability of Ca3N2 and (Ca3N2)3 clusters are higher than that of other clusters.