Van Gaal has been made to pay for United’s poor Premier League campaign and will be replaced by former Chelsea boss Jose Mourinho.
His Dutch coaching staff – including United assistant coach Albert Stuivenberg and goalkeeper coach Frans Hoek – have also left the club with immediate effect.
The United executive vice-chairman informed Van Gaal he will no longer continue as manager as they look to appoint Mourinho as his successor.
Van Gaal arrived at Carrington at around 8.45am. His entire coaching staff were also present as they learned their fate.
Mourinho expects to have more talks on Tuesday ahead of signing a three-year deal with his long-term assistant Rui Faria and goalkeeping coach Silvino Louro expected to follow.
Ryan Giggs’ future at United is up in the air despite Mourinho’s wish to keep the Welshman at the club.