Being a ninja is mainly tied to gaining new abilities. Lots of ninjas in Naruto made it their main aim to get their hands on information that would allow them to master new jutsu. However, this is not the most prudent approach as it involves taking many risks, and most of the time, these characters found their way to an early grave.
Only a few characters in Naruto managed to live until they were old and gray. While these characters were not necessarily the strongest physically, the experience that they had gained over the years helped them to outsmart their opponents in combat.
9 Hiruzen Sarutobi
Hiruzen Sarutobi was the Hokage of the Hidden Leaf. His talent was so great that he managed to earn the title of "God of Shinobi" without any Kekkei Genkai. Hiruzen also managed to learn about all the different kinds of techniques, including many forbidden ones as well.
Hiruzen ruled as the Hokage twice. The first time, his reign started after Tobirama named him his successor, and the second time was after Minato's sudden death when he was offered to rule as the Hokage once again. Hiruzen is the only Hokage who managed to grow old. At the time of his death, he was 68–69 years old.
8 Kakuzu
Kakuzu was the oldest member of the Akatsuki. He lived during the time of the first Hokage, whom he tried to assassinate. The attempt ended in failure, and after returning to his village, Kakuzu killed the elders and became a rogue ninja.
At some point, Kakuzu developed an obsession with money, and he would only do things that would give him a great deal of money. Kakuzu also developed a technique that allowed him to steal the hearts of others, and this technique helped him to prolong his life and made him almost immortal. Kakuzu was eventually killed by Naruto and co., and at that time, he was 91 years old.
7 Onoki
Onoki served as the Tsuchikage of the Hidden Stone Village for a very long time. He came to power after Mu's death, who was his mentor. Onoki had the ability to use Dust Release, a Kekkei Tota technique that can turn anything to dust.
In Naruto Shippuden, Onoki used his vast experience to help the Shinobi Alliance in the war against Obito Uchiha. He was the only Kage who was able to do serious damage to Madara Uchiha and his shadow clones. Onoki's age during Naruto: Gaiden was 100, which makes him one of the oldest characters in the series.
6 Madara Uchiha
Madara Uchiha is one of the most legendary characters in the series. He led the Uchiha clan during the Warring States Period, but after losing too many family members, he decided to ally with the Senju clan and put an end to all the bloodshed.
Sadly, Madara's happiness was cut short by the fact that all the villagers, including his own people, shunned him. So, he decided to launch an all-out war against Hashirama and the Hidden Leaf. In the decisive fight against Hashirama, Madara was defeated, but he did not die. He managed to survive because of the Demonic Statue of Outer Path, and he patiently waited until he found a suitable candidate who would help him accomplish his goals. Needless to say, Madara would have been well over 100 years old when he finally decided to die.
5 The Tailed Beasts
The tailed beasts were created after Hagoromo decided that his time was coming to an end. So he chose to split the chakra of the Ten-Tails into nine different-tailed beasts.
The nine-tailed beasts have unique abilities and varying amounts of chakra. When they were created, the Tailed Beasts were able to roam freely without any problems, which implies that there were no hidden villages that wanted to capture them. It is difficult to give an exact number, but they would be over 100 years old.
4 Gamamaru
Gamamaru also known as the Great Toad Sage, is the oldest toad living on Mt. Myoboku. He was famous for his prophecies, which would always come to be true. He bore witness to Kaguya enslaving the entire human race with the Infinite Tsukuyomi. Gamamaru was the one who revealed the truth about Kaguya to her sons, Hagoromo and Hamura.
The toad also taught the two brothers how to use senjutsu in order to fight against their mother. His exact age is unknown, but considering the fact that he was able to teach Hagoromo and his brother, he would have to be over a thousand years old.
3 Hagoromo Otsutsuki
Hagoromo Otsutsuki is one of the strongest characters in the series. He was the first person to rebel against Kaguya Otsutsuki. Hagoromo's power was so immense that he was able to fight his mother for several months. After successfully defeating Kaguya, Hagoromo became the jinchuuriki of the Ten-Tails.
This helped him to gain even bigger chakra reserves. Considering the fact that Hagoromo was born many years prior to the current storyline, he would easily be over a thousand years old.
2 Zetsu
Zetsu was one of the main antagonists of the series. It was the manifestation of Kaguya Otsutsuki's will. It came into existence after Hagoromo and Hamura had sealed away their mother.
Zetsu waited in the shadows until he finally found Indra Otsutsuki. It used its cunning to manipulate the Otsutsuki and turned him against his brother, Asura. As Zetsu existed way before the time of the ninjas, it is among the oldest characters in Naruto.
1 Kaguya Otsutsuki
At the top of the list, is Kaguya Otsutsuki. She came to Earth many centuries ago to steal the chakra fruit. She eventually ended up consuming the chakra fruit after which she placed the world under Infinite Tsukuyomi.
Kaguya ruled without any resistance until her sons rebelled against her. The fight between them lasted for a very long time, and eventually, her two sons managed to see her away forever. There is no doubt that Kaguya is the oldest character in the Naruto series.