The 19-year-old player is now ninth, behind American legend Serena Williams, winner of 23 Grand Slams, on the list released on Monday.
Iga is the only new entrant in the Top-10 following her title triumph against the Czech Republic's Karolina Pliskova in the Italian Open on Sunday. The top three slots continue to be retained by Australia's Ashleigh Barty, Japan's Naomi Osaka and Romania's Simona Halep, respectively.
With her title run in Rome, Iga becomes the fifth teenager to make her top 10 debut since 2008, joining Canada's Bianca Andreescu, Switzerland's Belinda Bencic, Belarus' Victoria Azarenka, the Netherland's Caroline Wozniacki, and Poland's Agnieszka Radwanska.
Prior to winning the French Open in October last year,