PSG travel to Stamford Bridge with the tie level at 1-1 following the first leg at the Parc des Princes, however, Chelsea hold a slight advantage courtesy of their away goal in the French capital.
Luiz left Chelsea for PSG in a £50 million move last June after his only season under the stewardship of Mourinho, who has long been referred to as "the special one".
But Luiz told a L'Equipe journalist: "He is special for you, not for me.
"I had some great moments at Chelsea and won a lot of titles. I was very happy.
"They are having a great season, defend well and have great players but above all I know my team. We will try to score there and play like we know how.
"We will have a good game plan and implement it the best way possible to achieve a great performance. Both can still qualify."
