By SABC Sport
11th July 2023
The 36-year-old utility back played 76 Tests for the Springboks between 2006 and 2020, winning World Cup winners' medals in 2007 and 2019.
He spent his last years playing for the Cheetahs and said in his post on Instagram that he had been struggling with a knee injury this year.
"It's been a tough few months coming to terms with saying goodbye to the game that has been my entire life," Steyn wrote.
"In answers to the many questions I have faced since sustaining a knee injury earlier this year, I am hereby announcing my retirement from professional rugby.
"To be honest, this is not how I envisioned the journey ending. Every player wants to end on their terms, but I am unfortunate to have played this game for so long and incredibly grateful for the journey I have had.
"I have given my everything ah I have no regrets.
"I have a massive number of people to thank from all around the world for the support throughout the highs and lows of my career. I will forever be grateful for the opportunities, the friendships, the memories and lessons that rugby has given me.
"I look forward to the next chapter and the opportunity to give back to the game that has given me everything. Thank you for the support. It has been a massive honour."
Steyn scored 165 points - including 11 tries - for the Springboks in his international career and was a key member of the victorious World Cup tournament in 2007 in France under head coach Jake White, where he played in the number 12 jersey for most of the campaign.
He was a world champion for the second time in 2019, this time playing a role off the bench as Rassie Erasmus' team clinched the trophy under captain Siya Kolisi in Japan.