Bob McCoskrie says he's not alone in resigning as a marriage celebrant over concerns about gay marriage, but other celebrants say they're not aware of resignations over the issue.
Mr McCoskrie, the Family First national director, has not renewed his licence as a celebrant because he rejects the state definition of marriage, he announced on his blog.
Referring to the passing of the Marriage Amendment Act, the post said the "act of cultural vandalism'' rammed through by politicians had prompted him to resign as a state-sanctioned marriage celebrant.
He would still perform marriage ceremonies for couples, but they would have to go to a local registry office to make the union legal.
"But it would be wrong of me - and perhaps even hypocritical of me - to allow myself to be appointed by the state to carry out that duty while rejecting the distorted definition that the state has adopted,'' he said.