Trainor and Legend sang " Like I 'm Gon na Lose You " on '' The Tonight Show Starring Jimmy Fallon '' on May 21 , 2015 . She performed the track solo in a set for '' The Today Show '' on May 22 , 2015 , along with " Dear Future Husband " , " All About That Bass " and " Lips Are Movin " . An a cappella rendition of the song by Trainor and Legend premiered on May 27 , 2015 , by '' Entertainment Weekly '' , as part of Pop TV 's " Massive Musical Mash-Up " . Trainor also performed the song alone on '' Jimmy Kimmel Live ! '' in July 2015 , and then along with Legend on '' The Ellen DeGeneres Show '' on October 14 , 2015 . Trainor performed the song on the American Music Awards of 2015 on November 22 , 2015 , in a medley with Charlie Puth 's collaboration " Marvin Gaye " . Girl group Fifth Harmony , with whom Trainor previously collaborated on their debut album '' Reflection '' , covered the song at the 2016 Billboard Women in Music ceremony , at which Trainor was supposed to perform but was unable to due to her vocal cords being damaged . The song was part of the setlist for Trainor 's The Untouchable Tour ( 2016 ) , where Trainor was joined by James Corden during a performance
American Music Awards of 2015
American Music Awards of 2015
Like I'm Gonna Lose You