Ninomiya Sontoku (二宮 尊徳?, September 4, 1787 – November 17, 1856), born Ninomiya Kinjirō (二宮 金次郎), was a prominent 19th-century Japanese agricultural leader, philosopher, moralist and economist.
Ninomiya Sontoku was born to a poor peasant family with a name of Kinjiro in Kayama (栢山) Ashigarakami-gun Sagami province. His father died when he was 14 and his mother died two years later. He was then placed in his uncle's household. While working in his uncle's land, Sontoku studied on his own. He later obtained abandoned land on his own and transformed it into agricultural land, eventually restoring his household on his own at the age of 20 and achieved considerable wealth as a landlord while in his 20s. He was then recruited to run his small feudal district which was facing considerable financial difficulty. He achieved this by reviving local economy, particularly through agricultural development. The daimyo, hearing of his achievement, eventually recruited Sontoku to run Odawara Domain then Sagami Province. It is said that during his administration a famine struck Odawara and Sontoku proposed opening up the public granaries to feed the starving populace. He was opposed by his fellow bureaucrats who reminded him that permission first had to be granted by the Shogun for commoners to have access to the rice stores. In that case, Sontoku replied, no one, including the bureaucrats, could eat the public rice before getting the Shogun's approval. They quickly changed their minds and decided that since it was an emergency, the people should be fed immediately. He was eventually entrusted with one of Shogunate's estate, which was great honour for someone of his low origin. His philosophy and methodology became a standard format in feudal land, developmental and economic management. The name "Sontoku" was given to him for his accomplishments. After his death, the emperor awarded him with Jyu Yoni, Lower Fourth Honour under the ritsuryō rank system.