It said since 2013, the number of people across the region identifying as "not religious" has risen from 8 per cent to 13 per cent. The rise is greatest in the under 30s, among whom 18 per cent identify as not religious, according to the research. Only Yemen saw a fall in the category.
The finding is one of a number on how Arabs feel about a wide range of issues, from women's rights and migration to security and sexuality.
More than 25,000 people were interviewed for the survey - for BBC News Arabic by the Arab Barometer research network - across 10 countries and the Palestinian territories between late 2018 and spring 2019.
On the other hand, most people across the region supported the right of a woman to become prime minister or president. The exception was Algeria where less than 50 per cent of those questioned agreed that a woman head of state was acceptable.
But the views change when it comes to domestic life, as most - including a majority of women - believe that husbands should always have the final say on family decisions. Only in Morocco did fewer than half the population think a husband should always be the ultimate decision-maker.
Meanwhile, the research suggested at least one in five people were considering emigrating in every country. In Sudan, this accounted for half the population. Interestingly, economic reasons were overwhelmingly cited as the driving factor.