The group will guest star on the episode as themselves opposite Miranda Cosgrove, Jennette McCurdy, Nathan Kress, Noah Munck and Jerry Trainor.
The plot revolves around the quintet performing their hit single 'What Makes You Beautiful' on Carly's live webcam show, when things go awry.
Made up of singers Harry Styles, Zayn Malik, Louis Tomlinson, Liam Payne, and Niall Horan, One Direction have shot to huge success in the US, with their album Up All Night going to number one on both the Billboard and iTunes charts.
Their appearance on iCarly marks just one in a series of US television appearances. The band will be performing tonight (March 31) at the Nickelodeon Kids' Choice Awards. They are also set to perform on an episode of Saturday Night Live.
However the boys recently quashed rumours of them having their own Nickelodeon show, similar to bands like Big Time Rush and the Jonas Brothers.
The One Direction episode of iCarly is scheduled to air April 7 on Nickelodeon.
Watch the One Direction iCarly promo below: