Robert Chambers, the so-called preppie killer who spent 15 years in prison for strangling a woman during what he called rough sex, has been sentenced to 19 years on a drug charge.

Chambers was sentenced yesterday after reaching a plea deal last month on charges of illegal sale of a controlled substance and assaulting a police officer. He would have faced life in prison if he had been convicted after trial.

The 41-year-old Chambers and his 39-year-old girlfriend, Shawn Kovell, were arrested in October at their Manhattan apartment on charges of dealing cocaine.

Kovell pleaded guilty in December, admitting they sold drugs in the apartment. The conviction was her first. She was spared prison and allowed to enter a drug rehabilitation program.

Upon completion of her program, Kovell will be allowed to withdraw the guilty plea and plead to a lesser charge so she can receive a sentence of probation.

Chambers initially pleaded not guilty to the charges. His lawyer planned to present a psychiatric defense at trial, arguing that his brain and judgment were damaged because of years of drug abuse. She had said he was using up to 12 bags of heroin plus other drugs each day at the time of his arrest.

Chambers made news in 1986 after the death of Jennifer Levin, an 18-year-old graduate of the exclusive Baldwin School, during a tryst in Central Park. The story was presented as a case of a privileged prep school youth gone bad.

Chambers pleaded guilty in 1988 to manslaughter in Levin’s death and was released from prison in 2003 after serving the maximum 15 years. He had forfeited chances at early release because of behavior problems behind bars, including involvement with drugs.

A year after his release from prison, Chambers was arrested for misdemeanor heroin possession and unlicensed driving. He pleaded guilty and was sentenced to 100 days in jail and was fined $200.