Shigeru Okada was born in Hiroshima Prefecture in 1924. He graduated from Tokyo Imperial University in 1947. After graduation, Okada joined Toei Eiga in October 1947; this is the company that preceded Toei Animation.

Okada's first produced work was Nihon Senpatsu Gakusei no Shuki: Kike, Wadatsumi no Koe. He also produced such works as Listen to the Voices of the Sea, Ako Roshi, Yoshiwara Enjo, The Geisha, Onimasa, Dai Nippon 'Teikoku, Father of the Kamikazee, Pod severnym siyaniyem, Shaso, Shogun Iemitsu no ranshin – Gekitotsu, Carmen 1945, Onimasa, 203 kochi, Moeru aki, Nippon no don: Yabohen, Yakuza senso: Nihon no Don, Karate Bear Fighter, Cherry Blossom Fire Gang, Queen Bee Strikes Again, Koroshiya ninbetsucho, Onsen konnyaku geisha, Three Pretty Devils, Inferno of Torture, Love and Crime, Mankiller, The Ghost-Cat Cursed Pond, The Magic Serpent, Eleven Samurai, Orders From Hell, and Bakuto.

Over the course of his time at Toei, Okada steadily rose his way through the ranks. In 1951, he served as the head of the company's Kyoto and Tokyo Studios. Under his tutelage, Toei was churning out more than 100 films annually.

In the 1960s, when television began to lure viewers away from the box office, Okada started producing "ninkyo" (code of honor) gangster films that were set anywhere from the end of the feudal era to the prewar days. These films usually featured loner outlaw heroes who upheld traditional gang values. At the end of the 1960s, Okada switched to gang films that focused on contemporary realities. This included the five-part Battles Without Honor and Humanity, which ran from 1973-1974. Unfortunately, his next four-part series, which ran from 1949-1979, did not achieve the same success as its predecessor.

Okada would go on to serve as Toei's president from 1971 to 1993. From there, he became the studio's chairman in June 1993. In 2002, he served as an advisor, and in June 2006, Okada became an honorary chairman. Okada was also a board director for Toei Doga, which later became known as Toei Animation, for four decades; he served in this role from 1972 until 2011. He also began serving as a director of Tokyu Recreation Co. Ltd. in March 2008.

Sadly, Shigeru Okada passed away from pneumonia on May 9, 2011 in a Tokyo hospital at the age of 87. He is survived by his wife Akiko and his son Yusuke. Yusuke is the current president of Toei Animation.