Globo media and other outlets say the man was fatally shot on Saturday on a highway outside the city.
Globo identified the man as Dean Tiessen and reported he is from Leamington, Ont., southeast of Windsor.
They're reporting he had been in Brazil since last month on a business trip for his agricultural company, New Energy Farms.
Foreign Affairs has confirmed a Canadian died in Brazil but is providing no other details, only saying consular officials are in touch with the family.
Tiessen's second cousin describes Dean Tiessen as a "very nice guy" with deep ties to the community.
Tiessen’s uncle, Victor Tiessen, told the Windsor Star his nephew was in Brazil on business and was supposed to return to Leamington Thursday.
"The family is just in shock, total shock," Victor Tiessen told the Windsor Star. "We still don't know what actually happened."
Victor told the Star he believes this was only the first or second trip his nephew made to Brazil to expand business ties. He said he was a family man and his wife and four kids are devastated by the loss.
(Windsor Star, The Canadian Press)