The 46-year-old will not be eligible to return until late October 2018.
In a statement, the PGA Tour said: “The PGA Tour announced today that Mark Hensby has violated the PGA Tour Anti-Doping Policy for failing to provide a drug testing sample after notification, and has been suspended for a period of one year.
“He will be eligible to return on October 26, 2018.
“The Tour will have no further comment on the suspension at this time.”
Hensby is currently ranked outside the world’s top 1,000 players but won the Scandinavian Masters in 2005 and the John Deere Classic in America a year earlier.
The 46-year-old made just two PGA Tour starts in 2016-17, missing the cut in each event.
Last year Hensby played 14 times on the Web.com Tour, making five cuts.
His best performances in the Majors were in 2005 when he tied for fifth at the Masters, shared third at the US Open and was equal 15th at the British Open.
In 2006 Hensby was injured in a car accident. Two years later, he lost his fully-exempt status on the PGA Tour.
The Victorian-born Hensby is the fourth player to be publicly suspended by the PGA Tour for violating its anti-doping policy, joining Doug Barron, Bhavik Patel and Scott Stallings.
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