Dr Barry Morgan, along with the incoming Children's Commissioner Professor Sally Holland and other prominent Welsh figures, urged politicians to repeal the legal defence of 'reasonable punishment' when they vote on the Violence Against Women bill.
Currently it's illegal for a parent to smack their child, unless using that defence. However this is not specifically defined in law, meaning it's judged on a case by case basis.
Physical punishment is considered 'unreasonable' if a mark is left on the child or if the child is hit with a something, like a cane or belt.
The Archbishop told Premier: "A lot of pressure has been on the government to accept an amendment to their Violence Aagainst Women bill to make it unacceptable to hit children as well.
"Leading academics, the former Children's Commisioner for Wales, the present Children's Commissioner for Wales, and psychiatrists are all saying that it's totally unacceptable for us to have the argument that it's reasonable to hit a child.
"If it's not reasonable to hit another adult, why should it be deemed reasonable and acceptable to hit a child? And I'm really hoping that this amendment will be accepted and that the Welsh government will give their AMs a free vote on it."
Churches across Wales have been holding vigils calling for a ban on smacking over the past few years.
You can read Dr Barry Morgan's letter calling for a ban on smacking here.
Listen to the Archbishop speaking to Premier:
