The 21-year-old left Premier League side Queens Park Rangers recently and Dons boss Karl Robinson has wasted no time in snapping-up the highly-rated youngster, after fighting off competition from a number of clubs.
Hitchcock agreed personal terms and passed a medical on Monday evening before finalising the switch on Tuesday. He trained with his new team-mates for the first time earlier today.
The Hertfordshire-born forward knows Sky Bet League 1 well having enjoyed successful loan spells at both Crewe Alexandra and Rotherham United in 2013/14. In total, Hitchcock scored nine goals in 19 appearances last season.
Speaking to MK Dons Player, Hitchcock said: “I’m buzzing and I can’t wait to get started. It’s exciting times for me.
“There were a few clubs interested but as soon as I knew MK Dons were in for me there was no other choice. I’ve played against them before and the football team play is really attractive and will suit me.
“I’m quite a clever player and I link-up quite well but it’s all about goals for me, really. I’ve just got to work as hard as I can and hopefully score a few.”
Hitchcock began his career with Blackburn Rovers having joined the club at youth level upon the recommendation of his father, ex-Chelsea and Watford goalkeeper Kevin Hitchcock, who was a goalkeeping coach at Ewood Park at the time.
In July 2011, Hitchcock joined League 2 side Plymouth Argyle on a three-month loan deal in an attempt to gain first-team football. He made his professional debut in a 1-1 draw with over Shrewsbury Town and went on to make a further nine appearances before returning to Blackburn in October.
However, Hitchcock left the Rovers the following February but soon signed a one-year contract with Queens Park Rangers. Despite not featuring for the R’s in the 2012/13 season, he did enjoy an impressive spell on loan with Bristol Rovers, scoring three goals in 17 appearances.
Hitchcock eventually made his debut for the Loftus Road club at the start of last season, scoring the winning goal late on after arriving as a substitute in the 83rd minute.
Featuring just once more for QPR, Hitchcock moved to Crewe on a short-term loan deal in November and went on to score three goals in six appearances before joining Rotherham on loan after Christmas.
Hitchcock enjoyed a successful stint at New York Stadium, with his five goals helping the Millers reach and, subsequently, won the League 1 play-offs. During his time in Yorkshire, he also scored his first career hat-trick in a 4-3 win over Gillingham.
His new manager Robinson told MK Dons Player: “Tom is somebody who I spoke to over the summer and he intrigued me.
“There are a number of strikers that we have looked at but thing about Tom is, he’s a natural goalscorer and the types of goals he scores are unique.
“He fits into the mould of player we’re trying to sign – he’s hungry, he’s enthusiastic and he’s a very talented individual.”