The Cottagers have given their survival hopes a huge boost in recent weeks thanks to back-to-back wins against Aston Villa and Norwich City.
Dejagah has now urged supporters to continue backing the team with plenty of enthusiasm as they try to stay in the top flight.
"It was a great atmosphere at Craven Cottage on Saturday, and also against Aston Villa," the midfielder told the club's official website. "So if the fans can do this in the next four games, I think and I hope that we will stay up.
"The fans helped us a lot in the last games. We are all together - the players, the staff and the fans - and hopefully we can get more points all together, starting on Saturday at Tottenham."
Fulham are currently in 18th place in the Premier League table, two points adrift of safety.