Bennett will join the broadcasting giant in April, leaving the role of general manager of Discovery, where she helped build The Learning Channel.
Bennett will be responsible for BBC One, BBC Two, the digital channels BBC Four, BBC Choice and the UKTV joint venture channels, and will oversee content on the international channels BBC America, BBC Canada and BBC Prime.
Bennett said: "This is an incredibly exciting time for the BBC with the reinvigoration of BBC One and BBC Two, the launch of the new channels and the challenge to keep raising the creative benchmark."
Bennett, a former BBC director of production, is renowned for her work on science and factual productions including Walking with Dinosaurs, Meet the Ancestors, Back to the Floor and The Human Body, a joint production between the BBC and Discovery Pictures.
At TLC, Bennett launched the "Life unscripted" branding campaign, which defined the network's diverse approach to programming.
In 2000, she was awarded an OBE in the Queen's Birthday Honours for services to science broadcasting.
BBC director general Greg Dyke said: "Jana's experience and success over the last two-and-a-half years, running a channel in the American multichannel market, gives her an invaluable perspective."
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