The 1573 Siege of Odani Castle (小谷城の戦い, Odani-jō no Tatakai) was the last stand of the Azai clan, one of Oda Nobunaga's chief opponents.

In September, 1573, Oda Nobunaga defeated the Asakura clan at the Siege of Ichijodani Castle.

Nobunaga took Odani Castle from Azai Nagamasa, who, left with no other option, committed suicide along with his father.

Their escape from the besieged castle became a fairly common sentimental scene in traditional Japanese art.

Before Azai Nagamasa committed seppuku he decided to make one last attack on Nobunaga's main camp; in the end, however, he failed and was instead captured.