Kaizan Oki was a student of Otsuki Mitsuoki (Otsuki Koko) and a central figure in the succession of highly skilled craftsmen that the Otsuki lineage produced during the late period. His common name was Naoichi, and he lived at Nijo in Kyoto. He initially signed his works as Oko, later changing the signature to Oki, and used art-names including Reibokudo and Chikufudo. The situates him within a direct line of distinguished Kyoto metalworkers that includes Otsuki Mitsuhiro, Kawarabayashi Hideoki, Tenkodo Hidekuni, and Matsuo Gassan, a group that "enjoyed a period of great prosperity."
Oki's characteristic technique centers on yobori high-relief carving executed on solid gold () or grounds, brought to completion with oki- and polychrome metal accents in gold, silver, , and . His display what the describes as "the unrestrained, open manner characteristic of Kyoto ," marked by an "outstanding power of direct observation." His chisel control is consistently praised as "smooth and expansive," capable of rendering delicate leaf veins with crisp precision while modeling adjacent forms with "rich fullness." In his earlier works signed Oko, the carving shows earnest strength in each stroke of and , though it "has not yet reached the fluent and fully flowing manner seen in works signed Oki" — a distinction the draws to chart his artistic maturation.
Across the record, Oki's work is characterized by compositions of "elevated tone and dignity," whether treating classical literary subjects such as Monogatari or rendering mythological figures with "powerfully masculine" force. The repeatedly affirms that his pieces "fully demonstrate the high technical level" of his art, describing them as works "in which Oki fully realized his abilities." His standing is summarized as that of "a key figure among Kyoto metalworkers," and his oeuvre reaffirms the continued vitality of the Otsuki school tradition at its highest level of accomplishment.