In a clip of the moment, the 21-year-old singer can be heard crying onstage as she tells fans that she's about to sing a song for her late Alaskan Klee Kai pet, adding that the two used to listen to Fleetwood Mac together all the time.
"It's gonna be hard for me to sing this next song. I'm not sounding myself, I don't feel myself," Cyrus said.
Before belting out a tearful rendition of the 70s hit song, the "Adore Me" singer opened up about Floyd's death to concertgoers.
"I'm sure you guys already know, but the reason that I'm so upset is my dog. I shouldn't say he was my favorite, but he was my favorite, and he passed away," she continued. "I just want to do a song for him. We used to always listen to Fleetwood Mac together. This is his favorite song...so I wanna do this song for Floyd. This song is 'Landslide.'"
Cyrus announced Floyd's death earlier on Wednesday via her Twitter account, saying she was having the "third worst day of her life."
[Jenna Eve via YouTube]