The former Newcastle and Crystal Palace manager takes the reigns at the Dutch outfit with the club struggling in 17th in the league, and will look to raise the spirits after the team were thumped 6-1 by Ajax at the weekend.
Pardew was watching from the stands for that game, and the club have confirmed the 58-year-old's appointment.
He takes over from Fons Groenendijk, with his assignment to keep the club in the Eredivisie after steering teams clear of danger in previous Premier League seasons.
Pardew called ADO Den Haag a "beautiful and warm club" and vowed to help motivate the struggling side to get them out of a "difficult period". Former Charlton Athletic boss Chris Powell will be Pardew's No2.