The France captain slammed home Madrid's second in a 2-0 win over Europa League winners Atalanta after Fede Valverde opened the scoring after the break.
Mbappe darted into space in the area and Jude Bellingham fed the forward who finished clinically in the 68th minute.
"We are at Real Madrid, we have no limit, if I can score 50, then 50, but the most important thing is winning and improving as a team, because we will win as a team," Mbappe told Movistar when asked if he was aiming to net 50 goals this season.
The forward has been linked with Madrid for years but was finally able to complete his dream move this summer at the end of his Paris Saint-Germain deal.
"It was a great night, I've been waiting for this moment for a long time," explained Mbappe.
"To play with this shirt, with this badge, for these fans, it's a gift for me.
"We won a trophy too, that's very important, we know that here we always have to win and I am very happy."
