Maki Kaji, the "Godfather of Sudoku," was a university dropout who converted a numbers game into one of the world's most popular logic puzzles.
His publisher in Japan has announced his death of bile duct cancer at the age of 69.
Kaji, who was born on Hokkaido's major northern island, founded Japan's first puzzle magazine after dropping out of Tokyo's Keio University.
After failing out of Tokyo's Keio University, Kaji founded Japan's first puzzle magazine.
In 1983, he established Nikoli and about the same time, he invented Sudoku.
In his eulogy, the major Japanese newspaper Mainichi credited Kaji with establishing puzzle sections in bookstores and for getting the word "Sudoku" into the Oxford English dictionary.
Kaji was the CEO of his puzzle firm, Nikoli Co., until July, when he died on August 10 at his home in Mitaka, a Tokyo suburb.
Maki has been travelling to over 30 countries to share his love of puzzles.
Sudoku became a worldwide sensation in 2004 after a New Zealand enthusiast pitched it and had it published in the British daily The Times.
Mr. Kaji remarked in a speech in 2008 that he originally "fell in love" with the game Number Place in 1984. Sudoku was the new name he gave it.