A method for the C-N coupling of imidazoles based on electrooxidative C-H functionalization of aromatic and benzylic compounds has been developed. The key to the success is the formation of protected imidazolium ions as initial products, avoiding overoxidation. Deprotection under nonoxidative conditions affords N-substituted imidazoles. Various functional groups are compatible with the present transformation. To demonstrate the power of the method, a P450 17 inhibiter and an antifungal agent having N-substituted imidazole structures were synthesized.