Odaira was born on January 15, 1874, in Ienaka, Shimotsuga, Tochigi Prefecture (present-day Tsugamachi Kassenba, Tochigi), the second son of Odaira Sōhachi and Chiyo.

[1] In 1900, he graduated from the electrical engineering department of Tokyo Imperial University.

Following his graduation, he joined a mining company as an engineer in its power plant.

This marked the beginning of the development that would become Hitachi, which was founded by Odaira in 1910.

However, because it was started as an in-house venture of the Kuhara Mining Company, the owner of Hitachi was Fusanosuke Kuhara, the president of the mining company, not Odaira.