The Incident at Honnoji (本能寺の変 Honnōji-no-hen) refers to the forced suicide in June 211582 of Japanese daimyo Oda Nobunaga at the hands of his samurai general Akechi Mitsuhide. This occurred in Honnoji, a temple in Kyoto, ending Nobunaga's quest to consolidate centralized power in Japan under his authority.

Akechi Mitsuhide had been a retainer to Nobunaga, but saw an opportunity to seize power, when not only was Nobunaga resting and unprepared for such an attack, but all the other major warlords were occupied in other parts of the country. Tokugawa Ieyasu was in Sakai, and Toyotomi Hideyoshi was busy sieging Takamatsu Castle.

After witnessing Nobunaga's death, Akechi Mitsuhide attacked Nijo Castle, also in Kyoto, and killed Oda Nobutada before proceeding to Azuchi Castle , where he was named regent.

Akechi Mitsuhide would be defeated by Toyotomi Hideyoshi two weeks later at the Battle of Yamazaki, losing to Hideyoshi all the power and authority his scheme had gained him.