What is the main religion of Haiti?

Roman Catholicism is the official religion of Haiti, but voodoo may be considered the country's national religion. The majority of Haitians believe in and practice at least some aspects of voodoo. Most voodooists believe that their religion can coexist with Catholicism. Most Protestants, however, strongly oppose voodoo.

http://countrystudies.us/haiti/33.htm

According to a 2010 survey by the Pew Research Center between 55 and 60 % of Haitians are Catholics and about 30 % are Protestants. In 2003, Haitian Vodou was granted official recognition by then President Jean-Bertrand Aristide. Aristide, a former Catholic priest, characterized Vodou as an "essential constitutive element of national identity."

https://en.wikipedia.org/wiki/Religion_in_Haiti

https://en.wikipedia.org/wiki/Haitian_Vodou