On a dramatic night at Stamford Bridge, goals from Andre Schurrle and Demba Ba saw Chelsea emerge 2-0 winners against Paris Saint-Germain.
The result ensured the Premier League giants progressed on away goals after overturning a two-goal deficit.
And the Chelsea captain said Mourinho's tactical preparation was the catalyst behind the club's successful night.
"We always gave ourselves a chance. We worked on different scenarios all week,' the 33-year-old veteran said.
"We had a game plan. Once again we got it right.
"We showed great character and a will to win. It was a big result. This competition means a lot to us.
"The manager has had a lot of success and so have we as a club."
Chelsea will contest their first Champions League semi-final since 2011-12, when they eventually went on to win their maiden European crown.
The London outfit defied all odds throughout that campaign under the guidance of former manager Roberto Di Matteo, upstaging Bayern Munich on penalties at Allianz Arena to lift the trophy.
Terry, one of four Chelsea players to miss the final due to suspension, believes the club can repeat that feat this season.
"When we got to the Champions League final and won it is the best feeling ever," he said.
"We have big players and we gave a big performance. That’s what we live for."
