The UK-based research group found 41-per-cent believe God does not have a human gender at all, while 36-per-cent reckon God is male.
Three-per-cent said God has a different human gender identity to male or female. Nineteen-per-cent said they were unsure.
The study also concluded that female believers are more likely (41-per-cent) to think God is male than male Christians (30-per-cent).
Catholics were found to be more convinced (47-per-cent) than Protestants (33-per-cent) to think God is a man.
Forty-three-per-cent of Protestants reckon God has no human gender - compared to 30-per-cent of Catholics, YouGov found.
The organisation said: "This... is perhaps ironic, as The Catechism of the Catholic Church #239, as laid down by Pope John Paul II in 1992, specifically states that 'God is neither man nor woman: he is God'.
"The vast majority of British Protestants follow the Church of England, which seems to still consider God to be male, although a movement within the Church called for God to be referred to as female in 2015.
"Other, smaller, Protestant denominations, such as Methodists and the United Reform Church, have previously introduced more gender-inclusive language for God."
According to the study, older Christians are more likely to believe (46-per-cent) that God has no human gender, compared to 37-per-cent of those aged between 25 and 49.
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