The Spanish giants are reported to be interested in Luiz, allocating up to £30million to sign the Brazil centre-back who returns from a knee injury for todays's Barclays Premier clash with Newcastle.
But unlike Arsenal, who have seen Cesc Fabregas and Alex Song depart for the Nou Camp in the last year, Di Matteo insists his European champions have nothing to fear.
"Luiz is part of our future. It's normal that he'll get interest because he's a Brazilian international centre back," the Italian said.
"There have been no approaches for Luiz and he's not for sale at any price.
"It doesn't concern me, the player will be here for the long term.
"I believe we can withstand Barcelona. Personally we don't feel any pressure from them. This club has been very successful in the past.
"I don't see why any players would want to leave us for anywhere else.
"We always compete for trophies. We're an ambitious club with an ambitious owner. We have great facilities.
"We have a great group of players who over the years have won a lot and still have the hunger to win more."
Chelsea have completed the signings of Spanish defender Cesar Azpilicueta from Marseille and Victor Moses from Wigan, taking the club's summer spending up to the £80million mark.
A club statement confirming the latter's arrival read: "Chelsea Football Club is delighted to announce the signing of Victor Moses from Wigan Athletic.
"The 21-year-old winger's last appearance in Wigan colours came in Chelsea's 2-0 win at the DW Stadium last weekend, when he caught the eye with his strong running out wide."
The challenge now facing Di Matteo is integrating his new players - who also include Eden Hazard and Oscar - into a winning team.
"It's going to be slow progress to get the players into the team, it won't be a revolution," he said.
"We want to build a team for the future. We have increased our creativity in midfield and have more pace.
"I'm happy with our signings. We've invested in the next cycle for four or five years."