The Uruguay forward penned a five-year contract for an undisclosed fee, ending speculation over his future after having been linked with a host of clubs including Manchester City and Real Madrid.
Cavani is expected to form a dream-team pairing with Sweden captain Ibrahimovic, who was named Ligue 1 player of the year after bagging 30 goals last season, and the 26-year-old is relishing the prospect.
"Fantastic!" he said on www.psg.fr. "Ibra is a champion, a world-class player and to play alongside him will be a pleasure. He's a winner, used to winning. It's a very positive thing and I hope to form a great attacking duo with him."
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PSG were crowned French champions last season for the first time in 19 years, and also reached the Champions League quarter-finals, and Cavani has vowed to give his all to bring more glory to the Parc des Princes.
"Yes, it's true that I'm joining the French champions that also did very well in the Champions League last term," he said. "I'm very proud and very happy to be here. I will give everything to help this team, this squad. They have signed a hard worker, a fighter."
He continued: "The sporting project at this club is very ambitious and a great source of motivation. I'm a competitor, one that always wants to win.
"Paris is one of those clubs in the world where everyone wants to play. The club is in a position to fight for the Champions League, which is an objective of mine."
Cavani produced three sparkling years for Napoli after signing from their Italian rivals Palermo in July 2010, scoring 104 goals in just 138 appearances for the Partenopei.
He was particularly prolific last term with 29 goals to help the Naples club finish second in Serie A, while his tally helped him win the Capocannoniere, which rewards the league's top scorer.
Cavani is just the latest big-money signing for the free-spending Parisians, who have recruited his former Napoli team-mate Ezequiel Lavezzi as well as Ibrahimovic, Marco Verratti, Lucas Moura, Javier Pastore and Thiago Silva in the last couple of years.
PSG president Nasser Al-Khelaifi believes the latest acquisition represents another piece of the jigsaw in making the club the kings of Europe.
"Our sporting project continues to take shape. The aims are to win the Ligue 1 championship and go as far as possible in the Champions League," he said.
"The signature of Cavani proves that our project is viable and allows us to continue to chase our goal, to make Paris St Germain the biggest club in Europe."
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