Vaughn's last time on the "Saturday Night Live" stage was 15 years ago during his debut appearance in 1998 when he was on to promote the "Psycho" remake.
R&B singer Miguel, a Grammy winner for the track "Adorn" from his 2012 album "Kaleidoscope Dream," will be performing on the show for the first time that evening.
Both will be making their second appearance on the sketch comedy series. Phoenix's fifth album "Bankrupt!" drops on April 22. McCarthy attracted high ratings and rave reviews when she hosted for the first time back in October.
McCarthy and Vaughn will both be on to promote their upcoming summer comedies. McCarthy stars opposite Sandra Bullock in "The Heat," which comes out on June 28, while Vaughn reunites with his "Wedding Crashers" co-star Owen Wilson for "The Internship," due in theaters on June 7.
The most recent episode of "SNL," hosted by Justin Timberlake, drew the show's highest ratings in 14 months since the Charles Barkley-hosted episode in January 2012.