Watanabe, 81, who will be presented with a trophy on June 20 in Cannes, is credited with building Shimbun Holding's media empire, which publishes national newspapers and magazines, and broadcasts on radio, TV and for film in Japan.
The company also owns The Yomiuri Shimbun, one of Japan's oldest and most successful broadsheets, which claims to have a worldwide circulation of 14m.
Watanabe joined The Yomiuri Shimbun in 1950 as a political writer and eventually became chief of the newspaper's Washington bureau in the 1970s, before being appointed managing director of the title in 1977.
He was made chairman of the editorial board in 1979, and later became senior vice-president in 1987. He was appointed chairman of the board of Shimbun Holdings in 2004.
Terry Savage, executive chairman of the Cannes Lions Festival, said: "Historically, Cannes Lions has always looked west when making this most important and prestigious award. This year we are looking east.
"In recognising Tsuneo Watanabe, we are honouring a leader who has contributed to building one of the greatest media organisations in the world, a leader who has the awesome responsibility of publishing the largest circulation newspaper in the world."
Former recipients of the award include Gunter Thielen, chairman and chief executive officer of Bertelsmann AG, who won it last year; Lachlan Murdoch, deputy chief operating officer at News Corp and the eldest son of Rupert Murdoch, who picked up the award in 2005; and Arnaud Lagardere, chairman and chief executive officer of Largardere Group, who was honoured in 2004.