Asano Tamotsu (died July 1864) was a Japanese nobleman and the heir to the Hiroshima Domain during the reign of his father Asano Norikatsu amid the Boshin War. In July 1864, he and his father defended Yoshida-Koriyama Castle against the Tokugawa Shogunate's armies, and he and his father died valiantly while defending their stronghold in the face of superior numbers and firepower.