Zouma made 32 Premier League appearances during a loan spell at Goodison Park last term, and the Toffees are reportedly keen to seal a permanent deal for the 24-year-old.
But after Zouma started Friday’s friendly defeat to Kawasaki Frontale in Yokohama, Lampard said he wants the France international to remain at Stamford Bridge.
“In terms of Kurt Zouma, he's a very good defender for us, very good player, very good person and professional,” Lampard told a news conference.
“I want him here, simple as that. We are competitive with the centre-backs we have in the team and he had a very good season at Everton. I can understand why they want him. He's a Chelsea player and I want him.”
Chelsea's transfer ban means they cannot sign new players, but Christian Pulisic made his first appearance for the club against Frontale, who won 1-0 thanks to a late Leandro Damiao header.
Kenedy and Mason Mount also featured in the J-League World Challenge clash as Lampard continues to examine his options ahead of the closure of the transfer window next month.
“In terms of Kenedy, my feeling coming into a big squad with a transfer ban was that I need to assess the players for as long as I can in pre-season, to make sure we pick a squad having had good eyes on them in training and in games,” added Lampard, who coached Mount at Derby County last term.
“I thought Mason’s performance was really good and it was a continuation of how he played for me last year and how he's trained for me since last Friday, as he's not been with us long.
“But his energy and his quality…Mason's part of the first-team squad this year and it's time for him.”
Pulisic's Blues debut also impressed Lampard, who tasted defeat for the first time in his third game in charge since succeeding Maurizio Sarri.
“He has been here a couple of days really in terms of training, so I have been really impressed," Lampard said of the United States international.
“He's comfortable on the ball and I think he should have had a penalty towards the end of the game.
“He wants to try to take people on, he's the sort of player the fans are going to like so we have to give him a little bit of time to adapt slightly. But the way he has trained, the way he has come in with his personality looks great so I am really pleased to have him.”