Out of 57 countries in a Win-Gallup survey, Ireland ranks 43rd in terms of individual religious beliefs.
The poll also shows Ireland as having the second largest decline worldwide in numbers claiming to be religious.
At the time of the last survey, in 2006, 69% of Irish people described themselves as religious.
Last year, that figure had declined to 47%.
Another 44% of the Irish people questioned described themselves as not religious compared to 23% globally.
Those surveyed were asked: "Irrespective of whether you attend a place of worship or not, would you say that you are a religious person, not a religious person or a convinced atheist?"
According to the poll, 10% of Irish people are convinced atheists, compared to 13% worldwide.
The poll also showed that 66% of the world’s poorest people declare themselves religious, compared to 49% in the highest-earning wage bracket. The most religious in the world are in Ghana, followed by Nigeria.
Meanwhile, China has the largest atheist population — 47% describe themselves as convinced atheist. Japan has 31% convinced atheists.
Fr Brendan Hoban of the Association of Catholic Priests said the numbers of religious had likely declined due to increased prosperity, education, greater independence, and the handling of child abuse complaints.
Kieran O’Connor, a sociologist at University College Cork, said the rapid distancing from religion was a direct response to the cover-up of abuse in the Catholic Church.
"Six years ago, we were affluent and educated. That change has not just materialised recently. So the Church’s handling of the abuse crisis has clearly affected our views of religion.
"Despite these results, as a people we all still engage with the rituals of religion: The marriage ceremonies, baptism, funerals, and Communion. Due to the homogenity of our society, we don’t tend to reflect on the other options."