A long signed Sukemitsu and dated in writing the twelfth day of the twelfth month of Shōan 3 (1301), 3 2 2.5 in length, is the fixed point for this smith. The Shōchū lists among the Yamato smiths a group whose names begin with the character , Sukemitsu, Sukehei, Sukenobu and Sukeyoshi, whose dates run from the end of into the middle period, and of these Sukemitsu, recorded as "Yamato, Shōan", is the oldest. The published sources state that signed works by the Yamato Sukemitsu are very few. They do not say with certainty to which Yamato line he belonged, but suggest that "he was probably a smith of the Senjuin group".
His name invites confusion, for the best-known Sukemitsu by far is Ki no Sukemitsu of the Yoshioka in . The published sources answer this from the tang. No two-character signature by the Yoshioka Sukemitsu has been seen, and the workmanship of the Yamato blades "is of course not work". The Yamato smith cuts a large two-character with a thick chisel in an angular hand, the strokes of and mitsu all forceful, and always above the . On the the commentary notes that "this two-character is exactly the same as that on the Tokyo National Museum blade", down to its position above the peg hole.
The usual manner is the Yamato one. The , first designated in the 11th session, is slender with , and a small , which the published sources call "a truly refined shape". Its is a tightly forged with fine, thick , - and fine . The is a mixed with , and small , entering well and a on the front, with and in the lower half and a bright with . The runs in a shallow and turns back shallowly in a small round. A second signed of the 21st session repeats the pattern: a slender, shortened blade, a tight with faint , a narrow with and frequent , the straight to a small round. The published sources call it "an extremely rare surviving work" sharing the manner of the other signed .
A second manner leans toward . The itself, with its closely packed , clear and bright with small , is said to have "a temperament", and the commentary concludes that this blade and the museum's dated together show two manners in his work, leaving his relation to the smiths for further study. A signed of the 25th session goes further. Its flows over the whole with a standing , and its temper is mixed with , slightly , deep in with , and , so that it looks at first like work. The published sources hold it to Yamato because "the adhering in both and differs", and conclude that it is "indeed by the same man as the Shōan-dated work". Taken together, they write, he "should be regarded as a Yamato smith". A shortened, unsigned of the 18th session is attributed to him, with an flowing to along the edge and a with . Its commentary places him within Yamato as "somewhat unusual among Yamato work".
The Shōan 3 survives as the Tokyo National Museum blade, and its inscription and length match the long recorded in Honma's inventory of the Imperial collection. There it is a long with high , and a medium . The flows and stands with , and the temper is a with small and , and , , and a tending to sink with . Below the written date a further inscription is partly illegible. Honma, who had examined two or three works he took for the same hand, knew this as the only one with a Shōan date, read the inscription as probably an owner's name, perhaps "a warrior monk of one of the great Yamato temples", and judged that "the workmanship is ordinary".
For the collector, the record is small. Fujishiro places him at Jō-jō . One stands at and three more blades at , four across the two tiers, together with the museum . No provenance is recorded for the privately held blades. His name is so overshadowed by the Sukemitsu that a signed Yamato example, with its bold two-character above the peg hole, is easily passed over; it appears on the market only very rarely, and is valued chiefly as a document of a little-known late Yamato hand.