Kira Yoshisada served as a bushō from the Sengoku to early Edo periods.  He was a retainer of the Tokugawa clan.

Yoshisada was born as the son of Kira Yoshiyasu.  His mother was the daughter of Matsudaira Kiyoyasu (the grandfather of Tokugawa Ieyasu).  Yoshisada was a cousin of Ieyasu.  His wife was the daughter of Imagawa Ujizane.

Yoshisada’s eldest son and designated heir, Kira Yoshimitsu, served in the Battle of Sekigahara.  After the war, a fief of 3,000 koku was awarded to the Mikawa-Kira clan.  By this time, it appears that Yoshisada has transferred headship of the clan to Yoshimitsu.

On 9/15 of Kanei 4 (1627), Yoshisada died in Mikawa Province.  He was sixty-four years old.  He was buried at the Jisshō Temple in Nishio in western Mikawa.  Later, he was reburied at the family temple of the Kira known as the Banshō Temple in Ichigaya in Edo.