Officers say 20-year-old Corinna Watson of Newark went to a home on Aug. 23 where her ex-boyfriend was staying.
Police say when the ex-boyfriend opened the door, Watson barged in and directed pepper spray at him.
Authorities say a 9-year-old girl, the daughter of the resident, was also affected by the pepper spray.
Police say Watson run away, but surrendered to police on Aug. 26.
She is charged with assault, burglary, endangering the welfare of a child and other offenses.