Mardini's house was destroyed in the Syrian Civil War.[8] Mardini and her sister Sarah decided to flee Syria in August 2015. They reached Lebanon, and then Turkey, where they arranged to be smuggled into Greece by boat with 18 other migrants, though the boat was meant to be used by no more than 6 or 7 people. After the motor stopped working and the dinghy began to take on water in the Aegean Sea, Yusra, Sarah, and two other people who were able to swim jumped into the water and pushed and pulled the boat through the water for over 3 hours until the group reached the island of Lesbos.[9] They then traveled on foot through Europe to Germany, where they settled in Berlin in September 2015.[6] Her parents and younger sister, Shahed, also fled Syria and live in Germany.[10]
International Olympic Committee (IOC) President Thomas Bach said of the refugee athletes, "We help them to make their dream of sporting excellence come true, even when they have to flee war and violence."[16]
"After the Olympics, I realised that it’s not just my story anymore. I realised that my responsibility is to raise awareness and bring hope to millions of refugees around the world and speak for all of those who do not have a voice".
In May 2017, Mardini became the youngest-ever Goodwill Ambassador for the United Nations High Commissioner for Refugees (UNHCR). Since then, she has met and encouraged refugees for example in Zaatari camp, Jordan, spoken at numerous high-level advocacy meetings and media interviews as well as in schools.[21] In October of the same year, Mardini joined a team of international athletes to represent the Under Armour sports brand. Chris Bate, Under Armour managing director in Europe, said: "We are inspired by her drive and accomplishments, both as a person and as an athlete."[22]
On 20 June 2023, the UN World Refugee Day, she officially started the Yusra Mardini Foundation to support sports and education for refugee communities. The Foundation is based both in the US and Germany, consisting of a small team that has been working with refugees before.[20] Presenting famous fashion brands, she was pictured in January 2023 on the cover of Harper’s Bazaar Arabia[23] and modelling at Milan Fashion Week in September of the same year.[24]
On 3 May 2018, her autobiography Butterfly: From Refugee to Olympian - My Story of Rescue, Hope, and Triumph was published.[29] In November 2022, a biographical film, inspired by Mardini's life and titled The Swimmers, was theatrically released and distributed on Netflix later the same month. The film stars Manal Issa, Nathalie Issa, and Ahmed Malek.[30]