Australia has no state religion A survey conducted in the year 2549 census, the population of 12.6 million people (64%) declared himself a Christian, of 5.1 million people (26%) are Catholic and 3.7 million (19%) is the Anglican way. Population 3.7 million people were classified as not religious. This includes the concept that a humanist atheism of Ay's popularity and rational population of nearly one million people (5%), other religions, including Buddhism, Islam, Hinduism and Jainism, despite a population of only 1.5 million people (. 7.5%) who attend church on a weekly basis.