The number of centenarians is expected to stand at 36,276 at the end of September, the health ministry said. Women account for an overwhelming 86 percent of the centenarians.
The government sends congratulatory cards to centenarians. Tomoji Tanabe -- who at 112 is the oldest man in the world -- accepted the card at his home in southern Miyazaki prefecture with cameras flashing.
Walking slowly but with no assistance, Tanabe said he ''wants to live 10 more years yet.'' He turns 113 next week.
''My biggest source of happiness is living like this and talking to everyone,'' he said. His other hobbies include keeping a diary and reading newspapers.
Tanabe, who lives with his son and daughter-in-law, has eight children, 25 grandchildren, 52 great-grandchildren and six great-great-grandchildren.
The world's oldest person is 115-year-old Edna Parker, who lives in a nursing home in the US Midwestern state of Indiana.
Japan has one of the world's highest life expectancy rates, which is attributed to a mix of factors including a traditional healthy diet with plenty of vegetables.
But Japan is also faced with a future demographic crisis as fewer young people start families, believing children are burdens to their careers, finances or lifestyles.