Incumbents
- Emperor: Hirohito
- Prime Minister: Yasuhiro Nakasone (L–Gunma)
- Chief Cabinet Secretary: Masaharu Gotōda (L–Tokushima)
- Chief Justice of the Supreme Court: Kōichi Yaguchi
- President of the House of Representatives: Michita Sakata (L–Kumamoto) until June 2, Kenzaburō Hara (L–Hyōgo) from July 22
- President of the House of Councillors: Mutsuo Kimura (L–Okayama) until July 22, Masaaki Fujita (L–Hiroshima)
- Diet sessions: 104th (regular session opened in December 1985, to May 22), 105th (extraordinary, June 2), 106th (special, July 22 to July 25), 107th (extraordinary, September 11 to December 20), 108th (regular, December 29 to 1987, May 27)
Read more about this topic: 1986 In Japan