51-year-old Dellmus Colvin entered a guilty plea on Friday morning in the September, 1987 slaying of 27-year-old Donna Lee White of Somers Point.
Colvin said he strangled White and dumped her body in a vacant lot in Atlantic City.
At the time of the killing, Colvin was charged with hindering and tampering with evidence.
The case was closed after an autopsy determined the victim died of acute cocaine intoxication.
It was reopened in 2009 after detectives discovered Colvin was being investigated for killing six prostitutes in Ohio.
He was already serving a life sentence.