Mikao Usui was born on August 15, 1865, in Taniai, Yamagata District, Gifu Prefecture, Japan, a village now incorporated into Miyama-chō. Surviving records portray Mikao Usui as an unusually wide-ranging student. His memorial inscription says that he read works on history and medicine, Buddhist and Christian scriptures, psychology, and Taoism. A recently recovered curriculum vitae written by Mikao Usui himself adds important details: he studied English, classical Chinese literature, law, psychology, and philosophy; received an elementary-school teaching license; worked in San Francisco from 1897 to 1898; and later helped establish and supervise schools in Tokyo under the auspices of an American women’s missionary organization. His memorial also states that he traveled in Europe, America, and China, although not every part of that account has yet been independently documented. Mikao Usui married Sadako Suzuki, and they had two children, a son named Fuji and a daughter, Toshiko.

In 1922, Mikao Usui undertook a twenty-one-day period of fasting and spiritual discipline on Mount Kurama, north of Kyoto. His memorial records that at the end of this retreat he experienced what it describes as a sudden encounter with “great Reiki,” after which he began applying the practice to himself and others. In April 1922, Mikao Usui established a teaching and treatment center in the Harajuku-Aoyama area of Tokyo, where he taught what became known as Usui Reiki Ryōhō. Ethical self-cultivation was central to his teaching. The precepts associated with Mikao Usui instructed practitioners, in essence, to refrain from anger and worry, cultivate gratitude, practice diligently, and show kindness to others, reciting these principles morning and evening. During the devastation following the Great Kantō Earthquake of September 1923, Mikao Usui and his students offered Reiki treatments to people affected by the disaster. As interest increased, he moved his center to Nakano in 1925; his memorial states that more than two thousand people eventually received instruction from him.

In the final years of his life, Mikao Usui traveled through Japan to teach, including visits to Kure, Hiroshima, Saga, and Fukuyama. He died suddenly in Fukuyama on March 9, 1926, reportedly after suffering a stroke. Mikao Usui was 60 years old by modern Western reckoning; his memorial gives his age as sixty-two according to the traditional Japanese method of counting age then in use. His family grave and the memorial erected by his students are at Saihō-ji Temple in Tokyo. The memorial, completed in 1927, remains one of the principal early sources for his life and teaching. Mikao Usui’s enduring contribution was a practice in which hands-on treatment was joined to daily spiritual discipline and ethical cultivation, an approach carried forward by his students and subsequently transmitted far beyond Japan.