Danjō was born in Japan on 12 December 1909.
Danjō was visited by city officials in 2009 to celebrate his 100th birthday.
Danjō passed away in Ōita City, Ōita Prefecture, Japan, on 16 June 2020, at the age of 110 years, 187 days.
On 17 June 2018, following the death of 111-year-old Kameo Ōya, he became the oldest living man in Ōita Prefecture, at the age of 108.
At the time of death, he was the second-oldest living man in Japan, behind Shōjirō Shirai. Following his death, then-107-year-old Masato Nakano became the oldest living man in Ōita Prefecture, and Motoi Fukunishi became the new second-oldest living man in Japan.
His age was verified by Japan’s Ministry of Health, Labour, and Welfare (MHLW), as well as Yumi Yamamoto and Yu Li, and validated by LongeviQuest on 29 December 2023.
* “21年12月14日 100歳のお誕生日を迎えられた方をお祝いしました” – Ōita City
* “100歳以上:県内873人 高齢化率、前年比0.6ポイント上回る あす敬老の日/大分” – Mainichi Shimbun, 16 September 2018 (local edition/Ōita, page 25)