Aguilera, 30, was a passenger in the car driven by her boyfriend, 25-year-old Matthew Rutler, when they were pulled over about 2:45 a.m. in the 1100 block of Clark Street. Spokesman Steve Whitmore of the Los Angeles County Sheriff's Department said deputies pulled the car over for erratic driving after hearing "burning rubber."
The Ford Mustang Rutler was driving was stopped on Clark Street just off the Sunset Strip.
Deputies booked Rutler for felony DUI. Rutler's blood-alcohol level was .09. He was released after posting $5,000 bail at about 9:30 a.m.
Whitmore said Aguilera was cooperative at the time of her misdemeanor arrest. It's unclear how much the 5-foot-2, 100-pound singer had to drink.
She was given a breath test, but the results will not be made public because she had no criminal intent, officials said.
Aguilera was booked, fingerprinted and placed in a cell by herself. She was released and turned over to one of her bodyguards after she sobered up at about 7:30 a.m.
Deputies have no intent of prosecuting the singer, saying Aguilera was taken into custody because she was too drunk to take care of herself.
"She didn't really understand where she was in many regards," Whitmore said. "She said she didn't drive, so she didn't even know where she lived."
The singer has been going through a divorce and child custody issues with her estranged husband, music marketer Jordan Bratman.
Aguilera also lost her footing at the Grammys and forgot some lyrics while singing the national anthem at the Super Bowl.