The Gunners boss, who is approaching 20 years in north London, has been under increased scrutiny from Arsenal fans in recent years.
“Arsene has been brilliant and I think it should be totally up to him when he chooses to leave," Ljungberg told the Daily Star.
“But when it happens I would like a manager who believes in an attacking and passing game. That's extremely important.
“There's a lot of great coaches out there but nobody can replace Arsene."