Japanese author and 1994 Nobel Prize for literature lauriate Kenzaburo Oe. (Photo: AFP)

Nobel-winning novelist Kenzaburo Oe, a leading liberal voice in Japan who challenged the conformity of modern society, has died aged 88, publisher Kodansha said on Monday.

"He died of old age in the early hours of March 3," the publisher said in a statement, adding that a family funeral had already been held.