Yoshisuke (義助) was the principal mainstream smith of the Shimada school of Suruga Province (Sunshū). According to sources, the first generation is placed in the Kyōshō era, with successive generations continuing the same name without interruption from the period through the era. However, it is difficult to distinguish these generations with precision, and among extant works, the earliest dated examples bear inscriptions from the Eishō era (1504-1521). The Shimada lineage in general is noted for their affinity with the workmanship of , , and traditions, and Yoshisuke stands as the school's most prominent representative.
The forging across designated works typically presents mixed with , often with the grain standing out () and a tendency toward near the edge, accompanied by and a somewhat whitish tonality. The ranges from mixed with to incorporating and , frequently with thick , , and . The characteristically shows , and the often exhibits . This repertoire demonstrates considerable versatility, from the archaic quality () observed in early-period to the forceful intensity found in later and . The school also produced comparatively many , and Yoshisuke's spearwork -- including ōmi- of substantial proportions -- exhibits an unbroken, well-composed style.
Yoshisuke's and are frequently encountered in with , often displaying thick and the distinctive withered () characteristic of the school. Several designated pieces bear skillfully executed , including relief carvings () of Myōō and openwork () -- the latter noted by examiners as an uncommon feature for this smith. The dated Genki 2 (1571) provides valuable documentary material for study of the lineage's later generations.