Ramos departed Real after 16 years of service where he won four Club World Cups, four Champions Leagues and five La Liga titles.
The World Cup winner had wanted to stay at the club after being offered a one-year contract but it was withdrawn and he was told the deal had expired.
Ramos said of PSG: “I am very happy to join Paris Saint-Germain. This is a big change in my life, a new challenge and it’s a day I will never forget.
“I am very proud to be a part of this ambitious project, to be a part of this squad with so many great players. Paris Saint-Germain is a club that has already proven itself at the highest level. I want to continue to grow and improve at Paris and help the team to win as many trophies as possible.”
The 35-year-old had struggled with injury last season which meant he only played once since March for Real. He was hoping for a two-year deal so his “family could have continuity and tranquillity”.
The withdrawal of the deal added salt to the wound as Ramos was left out of Luis Enrique’s Euros squad, who went on to lose their semi-final to Italy on penalties.
PSG chairman and chief executive Nasser Al-Khelaifi has called the defender “one of the greatest players of our era”.
He said: “Sergio is a complete footballer, one of the best defenders in the history of the game. He is a born competitor, a leader and a true professional. His vast experience and ambition is in perfect synergy with those of the club.”
Ramos is just one of many high profile signings that Mauricio Pochettino’s side have bagged in the transfer window.
Achraf Hakimi joined from Inter Milan on a five-year deal reportedly worth £61m and Georginio Wijnaldum signed from Liverpool in a three-year deal.
The big names don’t stop there as the club are close to announcing the arrival of goalkeeper Gianluigi Donnarumma on a free transfer from AC Milan.
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