AOL Huffington Post Media Group President and editor-in-chief Arianna Huffington made the announcement on Thursday, adding that Wilson's passion and humor make her the "perfect godmother" for the site, according to the Associated Press.
Huffington said that her and Wilson's Greek heritage set them up to place value on the aging process. The new site will be "both about news and about people sharing their own experiences about that stage in life."
The website is set to launch in August and Wilson will direct its vision and contact and also came up with the site's name, "Huff/Post 40."
"It's important to cover this with a sense of joy about this age... that's another thing that's often missing from the writing about this stage of life," Huffington said. "You worry about approval less - you're more clear about who you are - all those things are so liberating... It's an age where you can look less at the past and more into the future."
The 54-year-old actress has written editorial pieces on style and health for O, The Oprah Magazine and Harper's Bazaar, where she has been a contributing editor since 2006.
"Issues related to being over forty have always intrigued me," Wilson said in a press release. "My mom and dad always used to say, 'life begins at forty.' The idea that we boomers are somehow supposed to wind things down as we get older has completely escaped me. The Over 40s I have met are some of the most interesting, vibrant, curious, courageous, sexy, energetic people I know. Exploring the minds and hearts of this group of people is exciting. It's never too late to mix things up, change your life, to get to what you really should be doing - or want to be doing. As Mark Twain said, 'Age is an issue of mind over matter. If you don't mind, it doesn't matter.' I can't wait to get started."
Huffington has said she is not worried about Wilson's limited editorial experience, and said the actress is "a wonderful writer herself and she has a clear sense of what the theme of the site will be."
The website is currently filling the other top editorial positions and the media mogul plans on expanding the Huffington empire with Huffington Post France, Huffington Post UK, which launches on July 6 and Huffington Post Canada, which launched last month.
Wilson has starred in romantic drama films such as "Sleepless in Seattle" with Hanks in 1993 and "Runaway Bride" alongside Julia Roberts and Richard Gere in 1999. She also appeared in the 2009 film "It's Complicated", which starred Meryl Streep, Alec Baldwin and Steve Martin.
Wilson will next appear in "The Art of Getting By," which stars Emma Roberts and Eddie Highmore and hits theaters on June 17.