Casey O'Brien is an American professional ice hockey player who is a forward for the New York Sirens of the Professional Women's Hockey League (PWHL) and the United States national team. She played five seasons of college ice hockey at Wisconsin where she won three NCAA national championships and the Patty Kazmaier Award in 2025. She finished her career as Wisconsin's all-time leader in points (274) and assists (177), with her 274 points ranking eighth in NCAA history.