When Onoda landed on the island, he linked up with a group of Japanese soldiers who had been sent there previously. The officers in the group outranked Onoda and prevented him from carrying out his assignment, which made it easier for US forces to liberate the island when they landed on 28 February 1945. Within a short time of the landing, all but Onoda and three other soldiers had either died or surrendered and Onoda, who had been promoted to Lieutenant, ordered the men to take to the hills.
Towards the end of 1945 leaflets were dropped by air with a surrender order printed on them from General Tomoyuki Yamashita of the Fourteenth Area Army. Having already been in hiding for a year, and the only proof of the end of the war being this leaflet, Onoda and the others scrutinized every letter and every word on this piece of paper. One sentence in particular seemed suspicious; it said that those who surrendered would receive "hygienic succor" and be "hauled" to Japan. Again, they concluded it was an Allied hoax.
One of the four, Yuichi Akatsu, walked away from the others in September 1949 and surrendered to Filipino forces in 1950 after six months on his own. To the other three this seemed like a security leak and they became even more careful of their position.
In 1952 letters and family pictures were dropped from aircraft urging them to surrender, but the three soldiers concluded that this was a hoax. Shimada was shot in the leg during a shoot-out with local fishermen in June 1953, following which Onoda nursed him back to health, and on 7 May 1954 was killed by a shot fired by a search party looking for the men.
Kozuka was killed by two shots fired by local police on 19 October 1972, when he and Onoda burned rice that had been collected by farmers, as part of their guerilla activities, leaving Onoda alone. Though Onoda had been officially declared dead in December 1959, this event suggested that it was likely he was still alive and search parties were sent out, though none were successful.
On 20 February 1974, Onoda met a Japanese college dropout, Norio Suzuki, who was traveling the world and had told his friends that he was "going to look for Lieutenant Onoda, a panda, and the Abominable Snowman, in that order." Onoda and Suzuki became friends, but Onoda still refused to surrender, saying that he was waiting for orders from a superior officer.
Suzuki returned to Japan with photographs of himself and Onoda as proof of their encounter, and in 1974 the Japanese government located Onoda's commanding officer, Major Taniguchi, who had since become a bookseller. He flew to Lubang and on 9 March 1974 informed Onoda of the defeat of Japan in WWII and ordered him to lay down his arms.
Lieutenant Onoda emerged from the jungle 29 years after the end of World War II, and accepted the commanding officer's order of surrender in his uniform and sword, with his Arisaka Type 99 rifle still in operating condition, 500 rounds of ammunition and several hand grenades. This makes him the second-to-last fighting Japanese soldier of World War II, before Teruo Nakamura. Although many sources in modern culture poke fun at Onoda for "not believing the war was over," the primary motivation related to his devout belief in military discipline and honor: he had been ordered to never leave his post until he received a specific order enabling him to do so. Those orders did not arrive until 1974.
Though he had killed some thirty Philippine inhabitants of the island and engaged in several shootouts with the police, the circumstances of these events were taken into consideration, and Onoda received a pardon from President Ferdinand Marcos.
In 1980, after reading of a Japanese teenager who had murdered his parents, Onoda returned to Japan in 1984 and established the Onoda Shizen Juku ("Onoda Nature School") educational camp for young people, which is held at various different locations in Japan.
Onoda revisited Lubang Island in 1996, donating $10,000 for the local school on Lubang. His wife, Machie Onoda, became the head of the conservative Japan Women's Association in 2006. He currently spends three months of the year in Brazil.
He is an assenter of The Truth about Nanjing movie.