The singer confirmed the news to TMZ, which reported that she's being treated at Timberline Knolls near Chicago, the same facility Demi Lovato checked into for her addiction and eating disorder issues.
"I'm a crusader for being yourself and loving yourself, but I've found it hard to practice," the singer told the site. "I'll be unavailable for the next 30 days, seeking treatment for my eating disorder."
She added that her goal is, "to learn to love myself again, exactly as I am."
Ke$ha's rehab comes after she received praise -- and several magazine covers -- in 2013 for her slimmed down figure. In an interview with Self last year, Ke$ha dished about her diet.
"Eighty percent of the time I watch my portions and eat veggies and lean protein. It's excruciatingly boring, but it makes my body happy. The other 20 percent of the time, I do whatever I want. It's OK to sometimes eat [expletive] of chocolate!"