“It is with a deep sense of peace & gratitude that I have decided this will be my final season playing this beautiful game,” the 38-year-old posted.
“I never could have imagined the ways in which soccer would shape and change my life forever,” she added.
The two-time World Cup winner, well known for her activism, is part of the USA squad for the upcoming women’s World Cup in Australia and New Zealand.
Rapinoe plays in the National Women’s Soccer League (NWSL) for Seattle based OL Reign – their season concludes in November.
The winger currently has 199 caps over a span of 17 years playing for her country and also won an Olympic gold medal in London in 2012.
She was awarded the Best FIFA Women’s Player in 2019 but her fame came as much for her espousal of causes and her campaigning as for her skills on the field.
Rapinoe publicly came out as gay in July 2012 and has been a high-profile campaigner on social issues including LGBTQ+ rights, racial inequality and gender and pay equality.
She was a leading voice in the US women’s team’s successful fight for equal pay and conditions which resulted in a lawsuit and eventual new collective agreement being struck in 2021.
Rapinoe made headlines in 2016 when she took a knee during the national anthem in solidarity with NFL player Colin Kaepernick.
“I’ve been able to have such an incredible career, and this game has brought me all over the world and allowed me to meet so many amazing people,” said Rapinoe.
“I feel incredibly grateful to have played as long as I have, to be as successful as we’ve been, and to have been a part of a generation of players who undoubtedly left the game better than they found it.”
“To be able to play one last World Cup and one last NWSL season and go out on my own terms is incredibly special,” she added.
Last July she received the highest civilian honor in the United States when President Joe Biden awarded her the Presidential Medal of Freedom.
Rapinoe was the first footballer to receive the award and one of just six female athletes or coaches.
“Beyond the World Cup title to Olympic medals, Megan is a champion for essential American truth that everyone is entitled to be treated with dignity and respect,” Biden said at the award ceremony.
“She helped lead the change for perhaps the most important victory for anyone on our soccer team or any soccer team: equal pay for women.”
Rapinoe’s views made her a polarizing figure in the deeply divided country, however, as former USA men’s international now television pundit Alexis Lalas highlighted.
“Megan Rapinoe has transcended the game of soccer and she’s fearless and opinionated and interesting and she is a legend and she’s a badass both on and off the field,” Lalas said on Fox Sports.
“Now I fundamentally disagree with a lot of her opinions and stances off the field but I’ll fight to my last breath for her to have that freedom to express that which she has done incredibly well.
“I’ve got a lot of respect for her even though at times I disagree with her,” he added.
But Lalas questioned the timing of Rapinoe’s announcement in the build-up to the World Cup, where the USA are seeking a record-extending fifth title.
“I do think it’s a little weird to announce it before the World Cup and put that kind of attention on her,” he said.
US women’s team coach Vlatko Andonovski said Rapinoe remained an important part of the team for the World Cup which starts on July 20.
“Megan Rapinoe is one of the most important players in women’s soccer history and a personality like no other,” he said.
“It’s been a wonderful experience to coach her in the NWSL and for the national team and I’m looking forward to her being an important part of our team at the World Cup,” he added.
The Californian has spent most of her career playing in domestic leagues but had a brief spell in Australia with W-League team Sydney FC in 2011 and two years later played for French club Lyon, reaching the final of the Champions League.
At the 2019 World Cup in France, she scored in the 2-0 win over the Netherlands in the final and was named Player of the Match. She won the Golden Boot as top scorer and Golden Ball for best player in the tournament.