The 24-year-old from Oban received his official confirmation from Augusta National this afternoon after remaining in 44th spot in the rankings following the WGC-Dell Technologies Match Play in Texas.
MacIntyre will be making his debut at Augusta National, having already played in the other three majors over the past couple of years.
He tied for sixth in the Open Championship at Royal Portrush in 2019 before making the cut in both the US PGA Championship at Harding Park and US Open at Winged Foot last year.
MacIntyre will be among three players flying the Saltire in the opening men’s major of 2021 as he joins 1988 winner Sandy Lyle and Martin Laird.
After being crowned as European Tour Rookie of the Year in 2019, MacIntyre made his breakthrough on the circuit when winning the Cyprus Showdown in November.
He then broke into the world’s top 50 for the first time when finishing third in the Omega Dubai Desert Classic in February.
Meanwhile, one of MacIntyre’s closest friends on the PGA Tour, Billy Horschel, has jumped from 34th to 17th in the world rankings after he won the WGC Match Play.
Horschel beat fellow American Scottie Scheffler 2&1 in the final at Austin Country Club to land his victory on the US circuit and first individual title since the 2017 AT&T Byron Nelson in Dallas.
Dundee-based Frenchman Victor Perez finished fourth in the $10.5 million event after losing by the same margin to Matt Kuchar in the consolation match.