The Netherlands international has signed a four-year deal with the Red Devils after passing a medical at the club’s Carrington training ground on Monday.
Blind moved onto the Premier League’s radar this summer after the Dutch player of the year produced a string of eye-catching performances at the World Cup.
And the 24-year-old, who can play as a full-back or defensive midfielder, was thrilled to complete a move to the 13-time Premier League champions.
“It is a real honour to sign for Manchester United,” Blind told United’s website.
“I have been at Ajax since I was seven years old and I will always have very fond memories of the club and of my time there.
“Louis van Gaal is a tremendously talented coach, I have worked with him at Ajax and also for the Netherlands national team and I cannot wait to work with him at the biggest club in the world.”
Here is a selection of the best photos of United’s new signing Blind.
MORE: Man United latest news
MORE: Arsenal latest news
MORE: Chelsea latest news
MORE: Liverpool latest news