The Tatenokai (盾の会) or Shield Society was a private militia in Japan dedicated to traditional Japanese values and veneration of the Emperor. It was founded and led by the author Yukio Mishima.

The Tatenokai was created in 1967, recruiting its membership primarily from the staff of Ronso Journal , an obscure right-wing college newspaper. In an unusual move, the Tatenokai was granted the right to train with the nation's armed forces, the Japan Self-Defense Forces. In 1970 three Tatenokai led by Mishima briefly seized control of the Self-Defense Force's headquarters and attempted to rally the soldiers to stage a coup d'etat and restore imperial rule. When this failed, Mishima and Masakatsu Morita , the Tatenokai's main student leader, committed seppuku (ritual suicide).

Members

• Yukio Mishima, leader
• Hiroyasu Koga
• Masayoshi Koga
• Masakatsu Morita
• Masahiro Ogawa