Real scored their first league win at the Nou Camp since 2012, inflicting the first home defeat for Barcelona since February 2015.
"It is very important to have got the win here for our confidence and for the remainder of the season and with it coming right before our Champions League game in Germany," said Zidane.
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"We know just how important the Champions League is and we want to advance, so winning here in Barcelona was very important."
The Frenchman took over from Rafael Benitez at the start of the year and on Saturday came through his first big test with flying colours.
"I liked everything about my players' performance. We put in a massive effort and I was pleased with everything, both defensively and attacking-wise," said the 43-year-old, who as a player led Real to the Champions League title in 2002.
"When I see a team that is united and all together, with everyone fighting for their team mates and for their coach, there's nothing better."
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Zidane has every right to be satisfied with the form of Madrid as they aim to keep alive their unbeaten run in this year's competition in the quarter-finals.
They have won six successive games in all competitions since losing 1-0 at home to Atletico on February 27.
With Cristiano Ronaldo and Karim Benzema in goal-scoring form and Gareth Bale delivering assists, Real are an awe-inspiring prospect for mercurial Wolfsburg, struggling domestically this season.
Last year's Bundesliga runners-up and German Cup winners slumped to a 3-0 loss at Bayer Leverkusen on Saturday, putting European participation next season at risk.
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Wolfsburg, eighth in the Bundesliga, have also been struggling for goals in recent weeks, having scored just once in their last three league matches.
But Bast Dost, their top scorer last season, could make his comeback on Wednesday after being sidelined since January with a broken foot.
Wolfsburg sports director Klaus Allofs hopes the team will recover for what is the club's biggest European game to date and their first ever last eight appearance.
"It would be fatal if we did not look forward to this game, a Champions League quarter-final," Allofs said.
"We have to enjoy this but also make sure we correct some things from our Leverkusen performance. I am convinced we will see a different VfL on Wednesday."
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