"Twenty20 is just ripe for corruption - the shorter the game the more influence each particular incident can have," the former Australia off-spinner said in an interview in the March issue of The Wisden Cricketer magazine which goes on sale this Friday.
"So I think it opens up a great deal of opportunities for the bookmakers to try and corrupt players into providing various different outcomes in the game, if not the result itself.
Cricket needs to be very, very careful." May was also critical of the way the Indian Premier League's (IPL) dealings with players.
"The refusal to grant players the ability to review the security arrangements and the decision of the IPL and its franchises not to recognize or deal with any players' managers or agents, is self-defeating," he said.
"Its decision-making is very arrogant. The attitude is that they're the only game in town, they're the biggest game in town and, as long as they pay these huge amounts of money, they can do what they like. That may not always be the case."
Meanwhile in Mumbai, Indian Premier League commissioner Lalit Modi has denied reports that Deccan Chargers may refuse to defend the title because it is unhappy over a switch of venues for its home matches.
Several Indian newspapers have said that a law firm acting for the team had issued a legal notice stating that Modi's decision to switch its matches from Hyderabad and Visakhapatnam to other cities violated its franchise agreement.
But Modi said Tuesday on Twitter: "Reports that DC will not play or xyz may not - please ignore such news. All IPL teams will participate. You have my assurance on that."
