Atlantic City police responded to 1309 Caspian Avenue at 5:43 p.m. for a report of a shooting.
Upon arrival, they discovered a woman, identified as Jan Lynette Williams, 28, of Atlantic City, dead outside of the residence, of an apparent gunshot wound.
The second victim, Marlon Thigpen, 25, of Atlantic City, was transported to the AtlantiCare Regional Medical Center, City Campus, where he died later of his injuries.
Families of both victims have been notified, Atlantic County Prosecutor Ted Housel said.
Autopsies are scheduled for Thursday morning.
The Prosecutor's Office Major Crimes Unit is conducting the investigation along with the assistance of the Atlantic City Police Department.
Anyone with information is asked to call the Atlantic County Prosecutor's Office at 609-909-7800 or go to the Prosecutor's Office Web site at http://www.acpo.org/tips.html and provide information by filling out the form anonymously on the Submit a Tip page. People can also call Crime Stoppers at 609-652-1234 or 1-800-658-8477 (TIPS) or visit the Crime Stoppers Website at http://www.crimestoppersatlantic.com/. Crime Stoppers offers cash rewards for information leading to the arrest and indictment of those who commit crimes in Atlantic County.