Giles will be responsible for the day-to-day running of the website, working with both the editorial and advertising teams.
He will also continue in his role as international sales director.
Prior to joining Wallpaper in March 2005, Giles worked at Natmags for six years -- first as advertising manager and later as promotions director.
He began his media career in advertising sales for Express Newspapers.
Gord Ray, Wallpaper publishing director, said: "Ben has enjoyed brilliant successes during his time at Wallpaper and he is the ideal person for this new role, leading an increasingly important aspect of our business.
"We have very exciting plans for wallpaper.com in 2009 and I look forward to working with Ben to drive those developments forwards."
Wallpaper.com, which relaunched in 2004, claims to attract 500,000 unique users per month and 3m page views, and according to IPC ad revenues are up by 63% year on year in 2008.
Giles said: "Wallpaper.com is the fastest growing area of the Wallpaper brand and the aim is to make it the most creative, innovative and trend setting website in the world.
"I'm joining an amazing team and I can't wait to get started."