Police say Kamisha Richards was attacked inside the Cypress Hills Houses just after 10:30 p.m. Monday.
Richards was stabbed once in the chest and rushed to Brookdale Hospital, where she was pronounced dead.
She was apparently stabbed during a dispute that started as an argument with her boyfriend's sister over $20.
An 18-year-old woman was taken into custody following the stabbing.
Meanwhile, family members, including Richards' father, yelled in anguish outside the apartment complex.