Born the daughter of Honda Tadakatsu, she was adopted by lord Tokugawa Ieyasu, before marrying Sanada Nobuyuki.

Komatsuhime challenged Masayuki and Yukimura at the entrance of the Castle moments before of the Siege of Ueda.

Masayuki relayed a message to her: "I want to see my grandchildren", and in response, the princess emerged, dressed in full battle attire, saying, "Since we have parted ways in this conflict, though you are my father-in-law I cannot allow you into this castle.

After the Battle of Sekigahara, during Masayuki and Yukimura's exile, she took charge of sending them food and other daily necessities.

Komatsuhime was praised as a good wife and wise mother (ryōsai kenbo 良妻賢母).