A spokesman from the Department of Foreign Affairs confirmed the arrest late Thursday but did not release the man's name, citing privacy reasons.
However, both the Milwaukee Journal Sentinal and the Bangkok Post identify him as Antonius Ceulen.
The Journal Sentinal says authorities in Wisconsin charged Ceulen in 2005 with racketeering and that he is accused of defrauding investors out of $800,000.
The newspaper quotes American officials as saying they intend to ask that Thailand extradite him to the U.S. to face the charges.
The Bangkok Post says Ceulen, who is reported to be 60-years-old, was arrested at an apartment he shares with his wife, but it's not clear when he was arrested.
Neither media report indicated where in Canada Ceulen was from, but the Bangkok Post reported he went to Thailand sometime between 2000 and 2011.
Foreign Affairs says Canadian officials are in touch with local authorities and are providing consular assistance as required.