The troubled star sang on stage with the ROLLING STONES at the Isle of Wight Festival this summer.
But she pulled out of her support slot on part of the rockers' Bigger Bang world tour after her drug meltdown in August.
Now singer Mick has opened his heart on the industry's flawed new queen. Speaking in Germany, Jagger said: "Amy is a brilliant artist who makes fantastic music. She has class.
"But I'm worried she might die if she goes down the road that she has taken."