The striker is cup-tied for their first-leg clash against the Portuguese giants on Thursday night at the Stadium of Light.
While the Magpies were struggling to overcome Anzhi Makhachkala in the round of 16, the former Bordeaux star was watching his old side in action as they went down to a 4-2 aggregate defeat to Benfica.
And Gouffran, 26, has warned his team-mates about the attacking threat of Paraguayan striker Oscar Cardozo.
He told the Chronicle: "I watched their last game in Bordeaux when they lost 3-2 in the second leg.
"Benfica are a quality team with very good players, for example Oscar Cardozo.
"He has scored a lot of goals and is a danger - he scored twice against my old club in the second leg.
"We have to be very strong in Portugal to stop him."
Gouffran added: "We must try not to concede. If we can get through that without conceding we can make up the difference here in Newcastle.
"I have a lot of confidence in my team-mates. We are in with a chance. Everybody in the quarter-finals is. So we must keep going."