McCann Enterprise picked up the £3 million business without going through a formal pitch process.
The agency will initially develop a campaign for Toshiba's portfolio of consumer electronics products.
Toshiba appointed the start-up agency Johnny Fearless in June to help launch its tablet device, Toshiba TEG, in the UK and Europe. However, the launch of the product was subsequently shelved and Toshiba is no longer working with the agency.
Grey London previously handled Toshiba's advertising in Europe. Its last major campaign was 2009's "the space chair project", which involved sending a chair to an altitude of 98,000 feet.
Matt McDowell, the regional marketing director at Toshiba, said: "McCann Enterprise demonstrated strategic vision and creative flair."
