The Pew Research Centre analysed more than 4700 church fires which had happened in the US over the last twenty years, finding 51% were intentionally started.
This is considerably more than fires started at other buildings, with only 10% of non-residential fires and 5% of residential fires in 2013 classified as arson.
Analysts also found the number of church arson attacks was dropping slightly.
The Centre's report comes after a recent spate of arson attacks at Black-majority churches, all of which happened in the southern United States - an area historically known for racial tension.
The fires happened after the Charleston massacre, where a white gunman killed nine Black worshippers who allowed him to participate in their Bible study.
Since 1996, the American Bureau of Alcohol, Tobacco, Firearms and Explosives has been legally obligated to investigate every fire at a church, and classify whether it was accidental, a bombing, arson, undetermined or other (attempted arson, hoaxes and threats).
