The shooting happened around 10:54 p.m. on the 200 block of N. Harrison Street.
Police say officers responded to reports of gunshots.
Once they arrived on the scene they found the victim on the sidewalk with a gunshot wound to her torso.
She was rushed to Christiana Hospital where she was described as being in "very" critical condition.
A motive for the shooting remains under investigation.
The name of the woman who was shot has not been released.