The 22-year-old topped the list by earning an estimated USD 34.5 million from her movies from May 2011 to May 2012.
Stewart beat a number of A-list actresses who are more senior than her including her "Snow White and the Huntsman" co-star Charlize Theron. Theron places fifth with approximately USD 18 million.
"Stewart is an up-and-coming star. She is earning a lot of money from one of the most successful franchises of all time. This is who you would expect to see right now. This year you are seeing somebody young and at the brink of potentially great stardom sitting on the top of the list," said Forbes bureau chief Dorothy Pomerantz.
Trailing close behind Stewart is Cameron Diaz with an estimated USD 34 million, while Sandra Bullock lands on the third place with around USD 25 million.
"The Tourist" actress Angelina Jolie, who topped the list last year along with Sarah Jessica Parker, slips to the fourth place with an estimated earnings of USD 20 million.
Also included in the top 10 list are the likes of Julia Roberts, Meryl Streep, Kristen Wiig and Jennifer Aniston.
