Seitosha (正統社; fl. 1930 - 1949) was a Japanese publishing house active in Tokyo during the early to mid-20th century, particularly active during the wartime period of the 1930s and 1940s. Seitosha was known for official government publications, which, during this period, had a nationalistic and military leaning. During World War II, the Japanese government tightly controlled and censored publications, and Seitosha, like many other publishers, had to adhere to these strict regulations. After the war, with the democratization and demilitarization of Japan, many such publishing houses either adapted to the new environment or ceased operations. The fate of Seitosha is unclear, but we see no activity after 1950.