On Sunday, Luiz played no part of the FA Cup tie with Newcastle United due to an ankle problem, and the Brazilian international will stay on the sidelines for the game with Bournemouth on Wednesday night.
Luiz has been linked with a transfer to Arsenal, but Conte has only spoken about the defender's current fitness issues, rather than his future at Stamford Bridge.
At a press conference, the 48-year-old told reporters: "He's injured. He was injured two days before the game against Newcastle.
"An injury in his ankle. He's trying to recover and needs a bit of time to recover."
Luiz has played just 32 minutes of Premier League football since October 28.