Benteke, who made the £7m move to Villa Park from Genk last summer, has excelled for Lambert's men despite a frustrating season that sees them in 18th place.
And although Benteke has recently been linked with a move to Tottenham, Lambert is hopeful the 22-year-old will stay.
"We get linked with everyone but I don't pay too much attention to speculation," the former Norwich boss.
"We gave Christian the opportunity to go and perform and he has been excellent with the way he has performed and led the line. He has been excellent for us.
"What is he worth now? You'd have to have quite a lot of money to try and get him. In the modern day market, it can be whatever it wants."
Lambert also insisted Ashley Westwood is 'not a dirty player' after the midfielder was booked for a challenge on Jordan Henderson in Villa's clash with Liverpool last weekend.
Westwood may have been fortunate to escape a red card in the game after replays showed his studs connecting with the Liverpool midfielder.
Lambert added: "He's got the ball. I know what people are saying because of the way he's gone in but he has actually got the ball.
"If he had got the lad, then it's a different matter. You are not sitting telling me that Westwood is a dirty player. He's nowhere near that."