The 28-year-old won the last of his 31 caps in the RBS 6 Nations clash with Ireland last year and hasn't taken to the field for Ospreys since March 2009.
The former British Lion, who has twice won the Grand Slam, has been on unpaid leave in recent months but has been linked with a switch to Wasps as speculation mounts he is poised to end his exile.
And with the World Cup in New Zealand just a year away, Henson said: "I've never been to a Rugby World Cup which is coming up in 2011 and I'm thinking about training for that.
"Hopefully I can get back into rugby, do well and get into the World Cup squad. It's the one thing that is not on my CV."