Benitez believes that Lampard's experience could prove crucial in ending a run of seven Premier League games without a win.
He told reporters: "It is positive that he is back because we need character, we need numbers, and Frank is an experienced player.
"We've got a good team and a strong squad, but we needed players with more experience, and he could make a difference. He adds something, finding players between the lines, getting into the box and scoring goals.
"He cannot be the box-to-box player he was 10 years ago, but he'll be important for us when we're in possession with the players we have up front, people with good movement and ability. You need someone to link with them, and he can play that role."