The American singer was due to hit the stage tonight alongside Little Mix but now OneRepublic will instead be performing.
According to the Daily Star on Sunday newspaper, Gaga has dropped all promotion of her new album Joanne after disappointing sales of comeback single Perfect Illusion.
Which sounds a little backwards to us...
Lady Gaga released Perfect Illusion last month and the song peaked at Number 12 on the Official Top 40 chart.
Not exactly a bad result by any means, but anyone who watches The X Factor knows just how fickle and tough the music industry is.
Apparently it's not just The X Factor gig that Gaga cancelled, also pulling out of an appearance on BBC One's The Graham Norton Show.
“Lady Gaga had been scheduled to come to London this week to promote her new album Joanne but she cancelled all her appearances a little over a week ago," a source claimed.
The X Factor is back live tonight at 8PM on ITV with Little Mix and OneRepublic.