Kutsuki Harutsuna served as a bushō during the Sengoku period.  Harutsuna served as the lord of Kutsukidani Castle in Ōmi Province.  The Kutsuki clan was a branch of the Takashima family.  His common name was Yagorō and he held the title of Assistant Vice Minister of the Sovereign’s Household.

In 1518, Harutsuna was born as the son of Kutsuki Tanetsuna, the lord of Kutsukidani Castle in Ōmi.  In 1527, Tanetsuna offered protection to Ashikaga Yoshiharu, the twelfth shōgun, in Kutsukidani after Yoshiharu was ousted from the capital of Kyōto by the Hosokawa and Miyoshi clans.

In accordance with a custom dating to his grandfather, Kihide, he received one of the characters from the name of Ashikaga Yoshiharu and adopted the name of Harutsuna.  Harutsuna’s younger brothers, Fujitsuna, Shigetsuna, Naotsuna, and Terutaka.  Among these, Fujitsuna and Terutaka each received one of the characters from Yoshiharu’s son, Ashikaga Yoshifuji (later known as Yoshiteru), the thirteenth shōgun of the Muromachi bakufu.

Harutsuna served in the hōkōshū, a military organ of the Muromachi bakufu under the direct control of the shōgun. Harutsuna dispatched forces to battle on behalf Yoshiharu against other daimyō.  On 4/21 of Tenbun 19 (1550), Harutsuna was killed in action against Takashima Etchū-no-kami at the Kawakami manor on Mount Tawara in the Takashima District of Ōmi.  He was thirty-three years old.  His eldest son, Kutsuki Mototsuna, inherited the headship of the clan at the age of two.