It happened around 9:31 p.m. at the Favors Liquor Store in the 1000 block of Walnut Street.
Investigators say Kendel Miller, 20, of the 500 block of W. 39th Street was one at least two men who tried to rob the store.
During the crime there was an exchange of gunfire between the robbers and the clerk. When police arrived, they found Miller on the sidewalk with a gunshot wound.
Miller was taken to Christiana Hospital, where he was pronounced dead at 10:15 p.m.
The clerk, a 55-year-old man, was not hurt.
No other suspects in this case have been identified.
Anyone with information is to call Wilmington Police at 302-576-3636.