United will face Crystal Palace at Wembley looking for their first major trophy since Sir Alex Ferguson departed at the end of the 2012/13 season.
Victory in the match could also help the cause of Van Gaal, whose job security has been the subject of intense speculation.
The Dutchman’s contract has another year to run but his position appears precarious following United’s failure to qualify for the Champions League and Jose Mourinho has been linked with the Old Trafford post.
However, Van Gaal insists that Saturday’s game is, first and foremost, about securing a trophy for the United players, staff and supporters.
“I think the interests of the club are much more important, and also the interests of the fans are much more important, than the manager,” he said
“Of course you have set your own aims and that is one of the aims I have had, always.
“But it is not good to speak about my interests, it is good to speak about the interests of the club. For the club, this is very important.
“I have read that the last FA Cup (win for United) was 2004, so it is a long time ago. It is always exciting when you are so close, but close is not enough, you have to win it.
“When you win silverware it is always important, because a qualification is not a title.”
