Midfielder Schweinsteiger has not played a competitive fixture since featuring in Germany's World Cup final victory over Argentina back in July due to a knee injury.
However, the Bayern vice-captain is fit for Saturday's Bundesliga clash with Hoffenheim after his four-month layoff - giving coach Guardiola a much-needed boost after this week's blow of losing skipper Philipp Lahm for around three months with a fractured ankle.
When asked if Schweinsteiger is available for the game at the Allianz Arena, Guardiola told his pre-match media conference: "He's in the squad, which is good news."
Bayern were hit with several injury scares during the international break, with the likes of Thomas Muller and Manuel Neuer sustaining minor problems while away with Germany.
But while Guardiola confirmed on Friday that all of his players have returned to Munich fit, he was left to lament the loss of Lahm - who retired from international duty after captaining Germany to World Cup glory - until the new year.
"He was my most important player, of course it's tough for us," the Spaniard added.
Bayern hit full stride with some fantastic form before the international break, and have not lost in any competition since their 2-0 defeat to Borussia Dortmund in the DFL-Supercup in August.
Ominously for the rest of the Bundesliga, the reigning champions' sit four points clear at the top of the table having dropped just six points all season.
However, although his team have won all six of their league matches at the Allianz this term - scoring 20 goals in the process - Guardiola is taking nothing for granted against a dangerous Hoffenheim outfit.
Markus Gisdol's side are fifth in the table, and claimed a memorable 3-3 draw on their last visit to Munich in March.
"They have exceptional strikers," Guardiola said.
