A 3-1 win over Hertha Berlin secured triumph for Bayern, who can repeat the success of the previous campaign as the chances of another treble remain alive.
"I am satisfied that we have done it," Guardiola, who replaced Jupp Heynckes last summer, told Germany's Sky Sports News "It's another title for this club and that's important.
"If you see how the boys worked under Jupp Heynckes already last season, they have got even better. That is the result of hard work.
"At the start of a season, you always hope that everything will be good but I wouldn't have thought that it would be this good."
Guardiola has now lifted three trophies during his first season with Bayern following wins in the UEFA Super Cup and the FIFA Club World Cup.