Inter had the greatest season in their history completing a historic Treble of Serie A, Coppa Italia and UEFA Champions League, becoming the sixth European club to complete the treble and the only Italian club to achieve this feat to date.

The main move on transfer was an exchange with Barcelona, between Zlatan Ibrahimović and Samuel Eto'o. From a tactical point of view, the line-up was not made up from this fact: Eto'o was himself a centre-forward. His partner was Diego Milito, acquired from Genoa, like the midfielder Thiago Motta. There were also the arrivals of the centre-back Lúcio and the playmaker Wesley Sneijder. Inter unveiled the season losing the Supercoppa Italiana, due to a 2–1 knockout against Lazio.

During the brief pause in September, Inter had four points in the league, which became 16 before the October pause. Meanwhile, the side had started its European adventure (from group phase) drawing in the first part of the stage: it was renamed the "group of death" due to the presences of only national champions, from Spain (Barcelona, who was the European defending champion), Ukraina (Dinamo Kiev) and Russia (Rubin Kazan). Inter retained the first place in Serie A without obstacles and managed to recover the Champions League gap, finishing the group in second placed behind Barcelona. In the round of 16, they defeated Chelsea (the club that José Mourinho coached from 2004 to 2007) via a 3–1 aggregate; in the quarter-finals, CSKA Moscow was beaten 1–0 in both legs. The last obstacle toward the final resulted - once again - Barcelona. Four days before the first leg, Inter won 2–0 over Juventus claiming the Italian title. The Spanish side lost the first leg, despite having scored the first goal (with Messi): the final score was 3–1, enough for Inter to progress to the final despite a 1–0 loss in the second leg, and down to 10 men with a red card to Thiago Motta. As result, Inter went to their first UEFA final in 12 years since the 1998 UEFA Cup.

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