| Ōmura Seiichi | |
| Native Name Lang: | ja |
| Office1: | Governor of Nagano Prefecture |
| Term Start1: | 15 January 1935 |
| Term End1: | 13 March 1936 |
| Office2: | Governor of Nagano Prefecture |
| Term Start2: | 11 January 1938 |
| Term End2: | 23 December 1938 |
| Office3: | Governor of Kanagawa Prefecture |
| Term Start3: | 23 December 1938 |
| Term End3: | 4 September 1939 |
| Office4: | Vice Minister for Education |
| Term Start4: | 1939 |
| Term End4: | 1945? |
| Term Start5: | 22 May 1946 |
| Term End5: | 24 May 1947 |
| Office7: | Director-General of the Japan Defense Agency |
| Primeminister7: | Ichirō Hatoyama |
| Term Start7: | December 10, 1954 |
| Term End7: | March 19, 1955 |
| Predecessor7: | Tokutarō Kimura |
| Successor7: | Arata Sugihara |
| Constituency8: | Okayama |
| Term Start8: | 21 November 1960 |
| Term End8: | 23 October 1963 |
| Birth Date: | 4 May 1892 |
| Birth Place: | Tsuyama, Okayama, Empire of Japan |
| Nationality: | Japanese |
| Alma Mater: | Kyoto Imperial University |
| Occupation: | Politician, Cabinet Minister |
was a politician and bureaucrat in the early Shōwa period Japan, who subsequently was a politician and cabinet minister in the immediate post-war era.
Ōmura was born in Tsuyama, Okayama. After his graduation from the Law School of Kyoto Imperial University, he entered the Home Ministry. He served as Governor of Nagano Prefecture from 15 January 1935 to 13 March 1936, and again for a second term from 11 January 1938 to 23 December 1938. He was then appointed Governor of Kanagawa Prefecture from 23 December 1938 to 4 September 1939. Later in 1939, he was Vice Minister for Education under Prime Minister Abe Nobuyuki. In 1943, he was made chairman of the Japan Student Services Organization.
After the end of World War II, during the American occupation of Japan, Ōmura served as Home Minister in the first Yoshida administration from 22 May 1946 to 24 May 1947. He was also appointed to a seat in the House of Peers in the Diet of Japan.
From 10 December 1954 to 19 March 1955, Ōmura served as Director-General for the Japan Defense Agency under the first Hatoyama administration.
Ōmura subsequently was elected a seat in the Lower House of the Diet from his native Okayama, and served for six terms from 21 November 1960 to 23 October 1963. He was awarded the Grand Cordon of the Order of the Sacred Treasure on 29 April 1965.