| Birth Date: | 7 October 1991 |
| Birth Place: | Fayetteville, Arkansas |
| Height: | 5 ft 10 in[1] |
| Weight: | 133 lb |
| Sport: | Modern Pentathlon |
| Coach: | Janusz Pyciak-Peciak |
Margaux Isaksen (born October 7, 1991) is a modern pentathlete from the United States who competed at the 2008 Summer Olympics in Beijing, China, the 2012 Summer Olympics in London, United Kingdom, and the 2016 Summer Olympics in Rio de Janeiro, Brazil. She placed 4th at the London Olympics after coming from behind but missed a medal.
Isaksen competed at the 2008 Summer Olympics at age 16.[2] She finished in 21st place in the women's modern pentathlon event.[3] She finished first overall in the women's modern pentathlon event at the 2011 Pan American Games.[4] This qualified her for the modern pentathlon event at the 2012 Summer Olympics where she placed fourth, despite having had mononucleosis only a few weeks before.[5] Isaksen went on to win the 2013 Rio World Cup, shortly thereafter.
Isaksen was born in Fayetteville, Arkansas. She lived in Fayetteville for most of her early life, and grew up riding horses. She has one sibling, Isabella Isaksen, who is also at the Olympic Training Center in Colorado Springs, competing internationally in modern pentathlon. Isaksen's father was the captain of a cruise ship. He died of colon cancer when his daughters were 2 and 6 months old, respectively.[6] Isaksen was raised by her mother, Kathleen West, until she moved in at the Olympic Training center in Colorado Springs, Colorado, sometime during her early teenage years.
On June 1, 2008, at the age of 16, Isaksen qualified for the 2008 Summer Olympics when she received an official Olympic invitation from the Union Internationale de Pentathlon Moderne due to her ranking on the pentathlon world ranking list for the Olympic qualifying period.[1]