Centre-back Williamson, 33, moved to Molineux on an 18-month deal from Newcastle United in January 2016 but only ever made a handful of appearances after being sidelined for a year through injury.
Meanwhile, 27-year-old midfielder Henry joined on an initial two-and-half year deal in January 2014 but fell out of favour this season and spent the majority of the campaign on loan to Bolton Wanderers in League One.
Richard Stearman spent seven years at Wolves before being sold to Fulham in 2015, but rejoined on loan this season with the hopes of earning a permanent deal. The club have now confirmed that they have no plans to offer him the chance to move back to the Midlands, however, and he will instead return to Craven Cottage ahead of next season.
Striker Andreas Weimann joined on loan from Derby County in the January transfer window and Wolves are now actively discussing making his switch permanent.
"As ever we would like to thank all those players who will be leaving us," sporting director Kevin Thelwell told the club's website. "With Richard and James, they have played their parts at different times in some of the club's major successes of recent years, and their contributions will always be well remembered.
"Mike was unfortunate to suffer through injury during his 18 months as a player here, but remained a consummate professional throughout, and also made some key contributions during the second half of this season.
"We wish all three players all the very best in their future careers."