Green entered his plea in a downtown L.A. courtroom Monday afternoon and through his attorney, Blair Berk, waived his right to a speedy trial.
"The Voice" judge agreed to surrender to the
Green, whose real name is Thomas DeCarlo Callaway, is accused of providing Ecstasy, also known as Molly, to the 33-year-old woman in July 2012.
A Los Angeles Police Department investigation into the singer began almost a year ago after the woman said he put the drug in her drink as they dined.
The woman said she woke up to find herself naked in the 39-year-old singer's bed. But after two rounds of investigations, prosecutors declined to file sex-related charges against Green, citing insufficient evidence.
Green has previously denied any wrongdoing.