The France international leads the scoring charts in this season's competition with 15 goals, which is just two behind Cristiano Ronaldo's all-time record in a single campaign.
That includes back-to-back hat-tricks in the knockout-stage wins over Paris Saint-Germain and Chelsea, and three goals across both legs against Manchester City in the semi-finals.
Benzema is enjoying his best campaign yet in front of goal and will look to round off 2021-2022 in style when Madrid faces Liverpool in Sunday's (AEST) final at Stade de France in Paris.
Asked what improvements he has seen in Benzema this season, Ancelotti said: "He has more personality and leadership now on and off the pitch.
"What has not changed is his quality, which is still top, and also his humility."
At 34 years and 160 days, Benzema is out to become the second-oldest player to score in the UEFA Champions League final after Paolo Maldini (36 years and 333 days) for AC Milan – also against Liverpool in 2005.
The 34-year-old has happy memories of playing against the Reds, having opened the scoring in Madrid's 3-1 victory when the sides met in the 2018 final in Kyiv.
Marcelo, who was also on the pitch that day and is seeking an incredible 25th trophy with Los Blancos this weekend, has also been impressed by Benzema's leadership qualities.
"He has shown that [leadership], though it's not just been this season," Marcelo said.
"His character and presence has helped the team a lot. He doesn't even need to talk for that. He plays great football for us."