Åsa Nilla Maria Fischer is a former Swedish footballer who played primarily as a central defender, having earlier spent significant parts of her career as a defensive midfielder. After developing at Verums GoIF, she played for Vittsjö GIK and Kristianstad/Wä DFF before establishing herself at Malmö, where she won consecutive Swedish league titles in 2010 and 2011. She later joined Linköpings FC before moving to Germany in 2013.
Fischer enjoyed some of the most successful years of her career with VfL Wolfsburg. During six seasons in Germany she became captain and helped the club win the UEFA Women's Champions League in 2014, multiple Frauen-Bundesliga championships and several DFB-Pokal titles. She returned to Linköpings FC in 2019 and finished her playing career there in 2022.
At international level, Fischer represented Sweden for more than two decades and earned 189 senior caps, scoring 23 goals. She won World Cup bronze medals in 2011 and 2019 and an Olympic silver medal at Rio 2016. Known for her physical presence, leadership and ability at set pieces, Fischer was also named Swedish Women's Footballer of the Year when she received the Diamantbollen in 2018.

In 2023, Fischer published the autobiography "Jag sa inte ens hälften", written together with journalist Anna Friberg, reflecting on her long career in elite football and the conditions surrounding the women's game.
After ending her professional football career in 2022, Fischer trained to become a police officer. She completed her police education in 2025 and began working in the Norrköping local police area.