Yasutaro Koide, who lives in the central Japanese city of Nagoya, received the formal designation on Friday as family and city dignitaries applauded.
Mr Koide was born on March 13, 1903 and worked as a tailor when he was younger.
He became the world`s oldest man after the death of Sakari Momoi, of Tokyo, in July aged 112.
He said his secret to a long life is not to overdo, adding that he also recommends "enjoying everything".
He does not drink or smoke. His favorite food is bread.
Mr Koide can still read the newspaper without glasses.
Three of his seven children, two of his nine grandchildren and one great-grandchild attended a ceremony at a nursing home where he was given a plaque and a green vase.
Mr Koide was beaming but teary-eyed as those attending applauded.
The Chunichi Shimbun newspaper quoted a granddaughter, Aya Kikuchi, as saying her grandfather once tended to be very strict about manners.
"He was very stubborn, but he got nicer with age," she said. "His lifestyle is one that avoids stress."
One of the world`s fastest-ageing countries, Japan has about 54,000 centenarians.
So many, in fact, that the government is reportedly considering scrapping or scaling back a 52-year-old programme that presents each person reaching the century mark with an ornate sake dish and letter of congratulations from the prime minister.
The world`s oldest person is Susannah Mushatt Jones, of Brooklyn, New York, who celebrated her 116th birthday on Monday.
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