The invention relates to a 1,2,3-triazole functionalized N-heterocyclic carbene binuclear nickel compound and a preparation method thereof and belongs to the field of organometallic chemistry. According to the 1,2,3-triazole functionalized N-heterocyclic carbene binuclear nickel compound, 1,2,3-triazole functionalized N-heterocyclic carbene is taken as a ligand, and the mole ratio of N-heterocyclic carbene to nickel is 1 to 1; the 1,2,3-triazole functionalized N-heterocyclic carbene binuclear nickel compound has a molecular structural formula shown in specification, wherein R1 is imidazole or benzimidazole, R2 is one of benzyl, n-butyl and phenyl, and X is either PF6 or BF4. The preparation method of the 1,2,3-triazole functionalized N-heterocyclic carbene binuclear nickel compound is simple, the binuclear nickel carbene compound is stable to air and moisture, and the distance among nickel atoms is relatively short, so that the compound has a metal-metal effect; by using the catalyst, cross-coupling reaction can be efficiently realized, and a variety of biphenyl derivatives can be obtained in the yield of being higher than 90%; the compound has very good functional group compatibility, is environment-friendly and can be extensively applied to fine chemical industry and pharmaceutical industry.