The singer of numbers such as "Let's Get Loud" and "Love Don't Cost A Thing" has hurtled upwards from the No. 50 slot she occupied last year in the magazine's ranking of the 100 most influential movie, TV, music and sports stars.
"The Latina...parlayed her position as a judge on American Idol into hit singles, increased album sales, an upcoming world tour, three new movies and a growing portfolio of endorsements," wrote Forbes, which measures the fame, power and earnings of the stars.
JLo, who last summer separated from Marc Anthony, amassed earnings over the past year of $52 million, more than double the $25 million she earned the previous year, according to the figures compiled by Forbes.
The star, who is of Puerto Rican origin, unseated New Yorker Lady Gaga, from the No. 1 spot on the list, with the former top celebrity falling to fifth place because she did not tour much recently, although she also earned $52 million and her influence on the social networks continues to be "tremendous".