The third siege of Odawara occurrs in 1590, and is the primary action in Toyotomi Hideyoshi's campaign to eliminate the Hōjō clan as a threat to his power.

The months leading up to it see hasty but major improvements in the defense of the castle, as Hideyoshi's intentions become clear.

Thus, despite the overwhelming force brought to bear by Hideyoshi, the siege sees little actual fighting.