The gunman shot the man several times in the back on the 2100 block of N Spruce Street shortly after midnight.
The victim was rushed to Christiana Hospital where he later died.
Police say the victim's identity remains unknown, but describe him as a black male between the ages of 18 and 20.
Anyone with information pertaining to the identity of the victim or circumstances leading to the shooting is asked to contact authorities at 302-576-3620. Callers may remain anonymous by dialing Delaware Crime Stoppers at 1-800-TIP-3333 or by visiting www.tipsubmit.com.