Dr Barry Morgan accused London of treating his country unfairly and claimed Scotland and Northern Ireland were getting a "better deal".
Speaking with the BBC he said the devolution settlement given to Cardiff was not a "just settlement".
The clergyman is leaving his role as the leader of the Church in Wales on Tuesday after 14 years.
The government rejected his claim and said the Welsh Assembly was getting more powers over "everyday decisions in their lives".
Dr Morgan told the Newyddion9 programme: "Devolution in Wales is a matter of equality and fairness and we have not reached that point yet, as far as Wales is in the question in my opinion.
"I don't believe the latest bill which was passed is a just settlement.
"Scotland and Northern Ireland have been given better deals than Wales."
