The incident happened Wednesday evening at 24th Street and Ocean Park Boulevard.
Officials said they answered a disturbance call and had to enter a residence through a window. They found a man repeatedly stabbing a woman.
Police ordered the suspect to stop. When he didn't, authorities said officers shot and killed the man, who is believed to be the victim's ex-boyfriend.
The woman was hospitalized in critical condition. She underwent surgery and is expected to survive.
No officers were hurt. The shooting remained under investigation.