AC Milan managed to score four goals over the two group games between the two sides earlier in the campaign, with the Italian champions coming away with a 2-2 draw at Camp Nou before succumbing to a 3-2 defeat in the return leg.
Valdes is expecting another difficult encounter with the Rossoneri at San Siro on Wednesday evening but is boosted by Barcelona's excellent nine-game winning run.
"Milan are always a very dangerous team," the goalkeeper told reporters on Monday. "We saw that in the group stage.
"They are a great team with great history. A tie against Milan, who are one of the biggest sides in Europe, will be difficult.
"But it is coming at a good time for us and it is vital that we try to play our usual game."
Despite the winning streak putting the Catalan side only six points behind Real Madrid in La Liga with an El Clasico at Nou Camp still to come, Valdes is not carried away by the talks of a title race upset.
"When we were 10 points behind we did not change our approach, and now that we're six behind, we will not do so either," the Spain international explained.
"We have to compete against each and every opponent and just try to collect the three points.
"The press has been saying that the league was impossible for us but the message has always been the same on our part: never give up.
"However, the six-point gap is still substantial. Only time and the games will decide if the deficit is reduced. We have no choice but to win every game and wait to see what happens."
Barcelona tackle Milan at San Siro on Wednesday before hosting Athletic Bilbao at Camp Nou at the weekend.