The Gunners are the most successful team in the competition's history having triumphed on 13 occasions, while the Red Devils are 12-time winners.
Here, Press Association Sport looks at some of the memorable cup encounters between the two heavyweights of English football.
Arsenal 3 Manchester United 2 – 1979 FA Cup final
Better known as the 'five-minute final' because of an explosive finish. There was very little remarkable about most of the match in front of an official attendance of 99,219 at Wembley. Indeed, Arsenal looked to be cruising thanks to first-half strikes from Brian Talbot and Frank Stapleton. But Gordon McQueen halved the deficit after 86 minutes before Sammy McIlroy bagged a dramatic equaliser. With extra-time looming, there was one final twist as, almost straight from kick-off, Arsenal broke forward and Alan Sunderland managed to get the final touch to Liam Brady's cross to hand the Gunners the trophy.
Manchester United 2 Arsenal 1 – 1983 FA Cup semi-final
The last four encounter at Villa Park 16 years later perhaps burns brighter in the memory but this fixture was compelling in its own right, with a teenager the hero for United. Ron Atkinson's men had to come from a goal down as Tony Woodcock gave Arsenal the lead, with England midfielder Bryan Robson levelling matters just before half-time. Seventeen-year-old Norman Whiteside struck a marvellous winner to send United to Wembley, where both the youngster and Robson bagged in the final replay against Brighton to lift the trophy.
Arsenal 1 Manchester United 2 – 1999 FA Cup semi-final replay
A riveting affair between two teams close to the peak of their powers that has gone down as one of the best cup clashes of all-time and was settled by Ryan Giggs as United moved a step closer to an unprecedented 'Treble'. Fellow winger David Beckham's curling free-kick had put Sir Alex Ferguson's men ahead while an equally mesmeric strike from Dennis Bergkamp levelled midway through the second half. Roy Keane's sending off looked to put Arsenal in the driving seat and United's hopes were hanging by a thread when Phil Neville fouled Ray Parlour inside the area in the final minute. Peter Schmeichel denied Bergkamp and, in extra-time, Giggs scored a breathtaking solo goal, driving into the area before rifling his left-foot effort past a helpless David Seaman.
Arsenal 0 Manchester United 1 – 2004 FA Cup semi-final
Arsene Wenger – so disconsolate at the 1999 loss that he lamented "the luckiest (team) won" – had seen his side win the two previous editions of the competition heading into the encounter. Which is more, Arsenal were on their way to becoming the first – and still the only – team to go undefeated in a Premier League season. But there would be no league and cup double as Sir Alex Ferguson's men once again proved their bete noire at Villa Park. Edu and Patrick Vieira both hit the frame of the goal but the sides were separated by Paul Scholes' strike from close range just after the half-hour mark. United would go on to comfortably beat Millwall in the final.
Arsenal 0 Manchester United 0 (Arsenal win 5-4 on penalties) – 2005 FA Cup final
Scholes was the villain as Arsenal gained a measure of revenge for the previous season's FA Cup defeat and United ending their record-breaking 49-game unbeaten league run the previous October. United actually dominated for large spells and Arsenal had the goalframe to thank for denying both Wayne Rooney and Ruud van Nistelrooy at the Millennium Stadium. The Gunners, meanwhile, were reduced to 10 men when Jose Antonio Reyes was sent off towards the end of extra-time. In the first FA Cup final to be decided on penalties, Scholes was the only one to miss from the spot, with Arsenal captain Patrick Vieira slotting home the winner.