The acquisition, which is subject to customary closing conditions, is expected to close in the second half of 2014.
Launched in June 2011, Twitch is a live video platform for gamers with more than 55 million unique visitors viewing more than 15 billion minutes of content produced by more than 1 million broadcasters, including individual gamers, pro players, publishers, developers, media outlets, conventions and stadium-filling esports organizations.
Commenting on the transaction, CEO Emmett Shear, said: “Amazon and Twitch optimize for our customers first and are both believers in the future of gaming.
“Being part of Amazon will let us do even more for our community. We will be able to create tools and services faster than we could have independently. This change will mean great things for our community, and will let us bring Twitch to even more people around the world”.