David Luiz was bought by Conte on the transfer deadline day from Paris Saint-Germain for a massive £32m. Chelsea had sold the player in 2014 to PSG for a world record £50m.
Speaking to ChelseaTV, Conte said: "I think David Luiz is a centre-back, he's played a lot of games in that position.
"I know sometimes he's played as a central midfielder but in my mind the idea is to utilise him in the right position which, for me, is centre-back. He's played with Chelsea previously and he will bring a good personality."
Along with Luiz, the Italian manager also bought Marcos Alonso from Fiorentina on five-year deal.
Conte further added: "We reached our targets, David Luiz and Marcos Alonso are two good signings for us. Now we have to work with them because I think they can improve our squad.
"We need to put them into our idea of football. Now we must work on our defensive situation and with the defensive line. We need to improve our physical and tactical condition.
"After the international break it's always very tough to restart because many players don't arrive back until the end of the week, but we must quickly find our concentration and be focused because we know we play a tough game against Swansea and we want to prepare in the best way."
Chelsea take on Swansea City in a crucial game week 4 encounter on Sunday evening. The Blues have started their season on a high as they won 3 out of 3 matches and are the top half of the league table.
The addition of Luiz and Alonso into the squad has definitely strengthened them.