Okami Harusuke served as a bushō during the Sengoku period.  Harusuke served as the lord of Yatabe Castle in Hitachi Province.

The Okami clan were members of the Hitachi-Oda clan.  In addition to the lineage associated with Harusuke, there were several other Okami families.

In 1532, Harusuke was born as the son of Oda Harutaka, a sengoku daimyō in Hitachi and the thirteenth head of the Oda clan.  Harutaka was later killed in an internal rebellion launched by his younger brother, Oda Akiie.

Harusuke wielded authority near the provincial border of Hitachi so he came into frequent conflict with the Satake clan.  In 1569, at the Battle of Tebaizaka, he fought as a member of the army of Oda Ujiharu.  At this time, he was shot in the chest with an arquebus fired by Daizō-bō, a priest in the Negoro Group who was under the command of Makabe Hisamoto.  This is one of the earliest known uses of an arquebus in battle in the area.

The individual said to be his father, Oda Harutaka, was born thirty-six years earlier so either one generation is missing, the birth year of Harusuke is in error, or there was no blood relationship (such that he was adopted after the death of Harutaka).