Luis Enrique's men cruised into the last four with a 2-0 quarter-final second-leg victory over Paris Saint-Germain on Tuesday, securing a 5-1 aggregate win.
And Barca will be joined by Bayern and ex-boss Guardiola, whose side produced a stunning comeback to turn around a 3-1 first leg deficit with a 6-1 victory against Porto at the Allianz Arena.
Bayern last met the Catalan club in the semi-finals of the 2012-13 Champions League, when Jupp Heynckes masterminded a 7-0 aggregate demolition of a Barca team coached by the late Tito Vilanova.
But Luis Enrique said: "I'm happy to hear that Pep [Guardiola] managed to qualify. I'm happy whenever good things happen to my friends.
"Many people thought they [Bayern] had no chance and they scored six goals despite some important absences.
"He proved once again what he can do as a manager and what Bayern are as a team. So yeah, I'm happy today to hear they made it."
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