The 'Send My Love' hitmaker was set to play at the Talking Stick Resort Arena in Phoenix, Arizona, on Wednesday night (17.08.16) as part of her 'Adele Live 2016' tour, but took to her Instagram account to reveal she has such a bad cold she can't sing.
In an emotional clip, she said: "Hello everyone, specifically everyone in Phoenix and Arizona.
"I can't do my show tonight, my second show here. I'm really, really sorry. I've had a cold for a couple days, and I've been pushing through it and I did my show last night and I loved it, but I pushed too hard. And my cold has gotten the better of me.
"As you can hear, even if I did the show, it wouldn't be very good.
"I'm really, really, really sorry to let anyone down.
"I've enjoyed my tour so much and cancelling shows is not something I want to do. I've pushed through a lot of things that I've been trying to sing all morning and warming up and nothing is really happening."
But the 28-year-old star - who has three-year-old son Angelo with partner Simon Konecki - insisted she will reschedule the concert at some point and "smash" her performance when she is feeling better.
She added: "I'm so sorry to let you down. I know lots of people would be flying in, from all over, it's the last thing I want to do but I have to look after myself because I've got so many more shows to do.
"I will reschedule this show I promise you and I will come back and I will smash it for you. I'm really, really sorry, have a wonderful evening without me."
She then blew a kiss to her supporters.
The superstar singer is in the middle of a 106-date world tour on which she is due to perform next at Los Angeles' Staples Center on Saturday (20.08.16).