The New Zealand international, 23, opted for a move to Elland Road after Leeds beat off competition from Wolves and late interest from Cardiff.
Wood becomes United’s fourth summer signing following the additions of Charlie Horton, Lee Erwin and Sol Bamba earlier this month, as Uwe Rosler’s squad continues to take shape for the new campaign.
“I think he’s another important piece in the jigsaw,” the head coach told the club’s official website . “We were looking for a number nine type –like Chris Wood is.
“He’s physical, strong and experienced in this league. He has potential to develop and has his best years in front of him.
“It’s exciting. He already has a proven goalscoring record and I think there are many goals to come. We think that he is the right player.”
Wood, speaking on Twitter about the move to Leeds, said: “I’m delighted to sign for Leeds. I can’t wait to get started. I’m looking forward to a great season.”
Wood, who joined Leicester from West Brom in 2013, scored 20 times during his 62 appearances in all competitions for the Foxes.
He found the net on the opening day of the Premier League season in Leicester’s 2-2 draw with Everton, but top-flight opportunities became limited for the striker and he subsequently moved on loan to Ipswich for the second half of 2014/15.
Wood’s career began in New Zealand – representing Cambridge FC, Waikato FC and then Hamilton Wanderers – before he made the switch to England with West Brom as a highly-rated youngster back in 2009.
Four years at the Hawthorns, which included loan spells at Barnsley, Brighton, Birmingham, Bristol City and Millwall, brought limited first-team chances with the Baggies, and he eventually joined Leicester permanently in January 2013 following a prolific loan stint at Millwall.
Wood ended that campaign with an impressive 22 goals from 43 appearances, establishing himself as one of the division’s hottest properties. He netted eight in 29 games during Leicester’s promotion-winning campaign and featured seven times in the Premier League last season.