Michael believes she is addicted to alcohol, cocaine and prescription drugs and she needs to return to rehab.
He thinks Lindsay may be going back to jail after assaulting a young woman in a nightclub and being charged with lying to police about a car accident earlier this week.
In an open letter to her 26-year-old daughter via HollywoodLife.com, he blamed all her problems to her addictions and pleaded with her to return to rehab -- for a sixth time.
"Do I believe Lindsay the new reports that Lindsay is drinking two litres of vodka a day? I believe she's drinking to drown her sorrows. When I was at the Chateau Marmont I saw bottles. People tell me what she's doing," he wrote.
Michael also agreed with US chat show hosts Kathie Lee and Barbara Walters that Lindsay's life could end tragically.
"I have the same fears. Why is it okay for them to talk about Lindsay and not me? I'm her dad," he added.