The 18-year-old midfielder is out of contract at the end of the season and he looks set to leave the Gunners.
And according to The Independent, United are targeting the England ace.
They say Arsenal are keen to tie down the youngster with a new deal but other clubs are willing to offer McGuane first-team football.
The Independent reckon United, Juventus, Manchester City, Napoli and a host of Championship clubs are keen.
McGuane captained England’s Under-18 squad last season and has featured for Arsenal’s Under-23 side this campaign.
“Man Utd are keen to sign Arsenal youngster Marcus McGuane”
Should McGuane leave the Gunners, he would cost a compensation fee.
Juve are leading the race to sign the highly-rated midfielder but United and City are determined to fight for the Arsenal ace.
McGuane would become United’s fourth summer signing.
He would follow Romelu Lukaku, Nemnaja Matic and Victor Lindelof to Old Trafford.