Guardiola, who won the league, the Champions League and the FIFA Club World Cup with Barca last year, previously won the award in 2009.
The former Spain midfielder finished above Real Madrid coach Jose Mourinho—the winner in 2010—and Manchester United manager Sir Alex Ferguson in a poll reflecting the opinions of experts from 81 different countries.
Speaking to the press on Friday, Mourinho said that Guardiola's success was "fully deserved".
The IFFHS, which is based in Germany, has been issuing the award since 1996.
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